Detector for optically detecting at least one object

ABSTRACT

A detector ( 110 ) for determining a position of at least one object ( 118 ) is disclosed. The detector ( 110 ) comprises:
         at least one optical sensor ( 112 ), the optical sensor ( 112 ) being adapted to detect a light beam ( 150 ) traveling from the object ( 118 ) towards the detector ( 110 ), the optical sensor ( 112 ) having at least one matrix ( 152 ) of pixels ( 154 ); and   at least one evaluation device ( 126 ), the evaluation device ( 126 ) being adapted for determining an intensity distribution of pixels ( 154 ) of the optical sensor ( 112 ) which are illuminated by the light beam ( 150 ), the evaluation device ( 126 ) further being adapted for determining at least one longitudinal coordinate of the object ( 118 ) by using the intensity distribution.

REFERENCE TO PRIOR APPLICATIONS

This application is a Continuation application of U.S. application Ser.No. 14/897,467, filed Dec. 10, 2015, now allowed; which is a 371 ofPCT/EP2014/061682, filed Jun. 5, 2014, the disclosures of which areincorporated herein by reference in their entireties. This applicationclaims priority to European Patent Application No. 13171901.5, filedJun. 13, 2013; and German Patent Application No. 10 2014 006 280.5,filed Mar. 12, 2014, the disclosures of which are incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

The present invention is based on previous European patent applicationnumber 13171901.5, the full content of which is herewith included byreference. The invention relates to a detector, a detector system and amethod for determining a position of at least one object. The inventionfurther relates to a human-machine interface for exchanging at least oneitem of information between a user and a machine, an entertainmentdevice, a tracking system, a camera and various uses of the detectordevice. The devices, systems, methods and uses according to the presentinvention specifically may be employed for example in various areas ofdaily life, gaming, traffic technology, production technology, securitytechnology, photography such as digital photography or video photographyfor arts, documentation or technical purposes, medical technology or inthe sciences. However, other applications are also possible.

PRIOR ART

A large number of optical sensors and photovoltaic devices are knownfrom the prior art. While photovoltaic devices are generally used toconvert electromagnetic radiation, for example, ultraviolet, visible orinfrared light, into electrical signals or electrical energy, opticaldetectors are generally used for picking up image information and/or fordetecting at least one optical parameter, for example, a brightness.

A large number of optical sensors which can be based generally on theuse of inorganic and/or organic sensor materials are known from theprior art. Examples of such sensors are disclosed in US 2007/0176165 A1,U.S. Pat. No. 6,995,445 B2, DE 2501124 A1, DE 3225372 A1 or else innumerous other prior art documents. To an increasing extent, inparticular for cost reasons and for reasons of large-area processing,sensors comprising at least one organic sensor material are being used,as described for example in US 2007/0176165 A1. In particular, so-calleddye solar cells are increasingly of importance here, which are describedgenerally, for example in WO 2009/013282 A1.

A large number of detectors for detecting at least one object are knownon the basis of such optical sensors. Such detectors can be embodied indiverse ways, depending on the respective purpose of use. Examples ofsuch detectors are imaging devices, for example, cameras and/ormicroscopes. High-resolution confocal microscopes are known, forexample, which can be used in particular in the field of medicaltechnology and biology in order to examine biological samples with highoptical resolution. Further examples of detectors for opticallydetecting at least one object are distance measuring devices based, forexample, on propagation time methods of corresponding optical signals,for example laser pulses. Further examples of detectors for opticallydetecting objects are triangulation systems, by means of which distancemeasurements can likewise be carried out.

In US 2007/0080925 A1, a low power consumption display device isdisclosed. Therein, photoactive layers are utilized that both respond toelectrical energy to allow a display device to display information andthat generate electrical energy in response to incident radiation.Display pixels of a single display device may be divided into displayingand generating pixels. The displaying pixels may display information andthe generating pixels may generate electrical energy. The generatedelectrical energy may be used to provide power to drive an image.

In EP 1 667 246 A1, a sensor element capable of sensing more than onespectral band of electromagnetic radiation with the same spatiallocation is disclosed. The element consists of a stack of sub-elementseach capable of sensing different spectral bands of electromagneticradiation. The sub-elements each contain a non-silicon semiconductorwhere the non-silicon semiconductor in each sub-element is sensitive toand/or has been sensitized to be sensitive to different spectral bandsof electromagnetic radiation.

In WO 2012/110924 A1, the content of which is herewith included byreference, a detector for optically detecting at least one object isproposed. The detector comprises at least one optical sensor. Theoptical sensor has at least one sensor region. The optical sensor isdesigned to generate at least one sensor signal in a manner dependent onan illumination of the sensor region. The sensor signal, given the sametotal power of the illumination, is dependent on a geometry of theillumination, in particular on a beam cross section of the illuminationon the sensor area. The detector furthermore has at least one evaluationdevice. The evaluation device is designed to generate at least one itemof geometrical information from the sensor signal, in particular atleast one item of geometrical information about the illumination and/orthe object.

U.S. provisional applications 61/739,173, filed on Dec. 19, 2012,61/749,964, filed on Jan. 8, 2013, and 61/867,169, filed on Aug. 19,2013, and international patent application PCT/IB2013/061095, filed onDec. 18, 2013, the full content of all of which is herewith included byreference, disclose a method and a detector for determining a positionof at least one object, by using at least one transversal optical sensorand at least one optical sensor. Specifically, the use of sensor stacksis disclosed, in order to determine a longitudinal position of theobject with a high degree of accuracy and without ambiguity.

Despite the advantages implied by the above-mentioned devices anddetectors, specifically by the detectors disclosed in WO 2012/110924 A1,U.S. 61/739,173 and 61/749,964, several technical challenges remain.Thus, generally, a need exists for detectors for detecting a position ofan object in space which is both reliable and may be manufactured at lowcost.

Problem Addressed by the Invention

It is therefore an object of the present invention to provide devicesand methods facing the above-mentioned technical challenges of knowndevices and methods. Specifically, it is an object of the presentinvention to provide devices and methods which reliably may determine aposition of an object in space, preferably at a low technical effort andwith low requirements in terms of technical resources and cost.

SUMMARY OF THE INVENTION

This problem is solved by the invention with the features of theindependent patent claims. Advantageous developments of the invention,which can be realized individually or in combination, are presented inthe dependent claims and/or in the following specification and detailedembodiments.

As used in the following, the terms “have”, “comprise” or “include” orany arbitrary grammatical variations thereof are used in a non-exclusiveway. Thus, these terms may both refer to a situation in which, besidesthe feature introduced by these terms, no further features are presentin the entity described in this context and to a situation in which oneor more further features are present. As an example, the expressions “Ahas B”, “A comprises B” and “A includes B” may both refer to a situationin which, besides B, no other element is present in A (i.e. a situationin which A solely and exclusively consists of B) and to a situation inwhich, besides B, one or more further elements are present in entity A,such as element C, elements C and D or even further elements.

Further, it shall be noted that the terms “at least one”, “one or more”or similar expressions indicating that a feature or element may bepresent once or more than once typically will be used only once whenintroducing the respective feature or element. In the following, in mostcases, when referring to the respective feature or element, theexpressions “at least one” or “one or more” will not be repeated,non-withstanding the fact that the respective feature or element may bepresent once or more than once.

Further, as used in the following, the terms “preferably”, “morepreferably”, “particularly”, “more particularly”, “specifically”, “morespecifically” or similar terms are used in conjunction with optionalfeatures, without restricting alternative possibilities. Thus, featuresintroduced by these terms are optional features and are not intended torestrict the scope of the claims in any way. The invention may, as theskilled person will recognize, be performed by using alternativefeatures. Similarly, features introduced by “in an embodiment of theinvention” or similar expressions are intended to be optional features,without any restriction regarding alternative embodiments of theinvention, without any restrictions regarding the scope of the inventionand without any restriction regarding the possibility of combining thefeatures introduced in such way with other optional or non-optionalfeatures of the invention.

In a first aspect of the present invention, a detector for determining aposition of at least one object is disclosed. As used herein, the termposition refers to at least one item of information regarding a locationand/or orientation of the object and/or at least one part of the objectin space. Thus, the at least one item of information may imply at leastone distance between at least one point of the object and the at leastone detector. As will be outlined in further detail below, the distancemay be a longitudinal coordinate or may contribute to determining alongitudinal coordinate of the point of the object. Additionally oralternatively, one or more other items of information regarding thelocation and/or orientation of the object and/or at least one part ofthe object may be determined. As an example, at least one transversalcoordinate of the object and/or at least one part of the object may bedetermined. Thus, the position of the object may imply at least onelongitudinal coordinate of the object and/or at least one part of theobject. Additionally or alternatively, the position of the object mayimply at least one transversal coordinate of the object and/or at leastone part of the object. Additionally or alternatively, the position ofthe object may imply at least one orientation information of the object,indicating an orientation of the object in space.

The detector comprises:

-   -   at least one optical sensor, the optical sensor being adapted to        detect a light beam traveling from the object towards the        detector, the optical sensor having at least one matrix of        pixels; and    -   at least one evaluation device, the evaluation device being        adapted for determining an intensity distribution of pixels of        the optical sensor which are illuminated by the light beam, the        evaluation device further being adapted for determining at least        one longitudinal coordinate of the object by using the intensity        distribution.

As used herein, an optical sensor generally refers to a light-sensitivedevice for detecting a light beam, such as for detecting an illuminationand/or a light spot generated by a light beam. The optical sensor may beadapted, as outlined in further detail below, to determine at least onelongitudinal coordinate of the object and/or of at least one part of theobject, such as at least one part of the object from which the at leastone light beam travels towards the detector.

As used herein, the term “longitudinal coordinate” generally refers to acoordinate in a coordinate system, wherein a change in the longitudinalcoordinate of an object generally implies a change in a distance betweenthe object and the detector. Thus, as an example, the longitudinalcoordinate may be a coordinate on a longitudinal axis of a coordinatesystem in which the longitudinal axis extends away from the detectorand/or in which the longitudinal axis is parallel and/or identical to anoptical axis of the detector. Thus, generally, the longitudinalcoordinate of the object may constitute a distance between the detectorand the object and/or make contributions to a distance between thedetector and the object.

Similarly, as will be outlined in further detail below, a transversalcoordinate may simply referred to a coordinate in a plane perpendicularto the above-mentioned longitudinal axis of the coordinate system. As anexample, a Cartesian coordinate system may be used, with a longitudinalaxis extending away from the detector and with two transversal axesextending perpendicular to the longitudinal axis.

As further used herein, a pixel generally refers to a light-sensitiveelement of the optical sensor, such as a minimum uniform unit of theoptical sensor adapted to generate a light signal. As an example, eachpixel may have a light-sensitive area of 1 μm² to 5 000 000 μm²,preferably 100 μm² to 4 000 000 μm², preferably 1 000 μm² to 1 000 000μm² and more preferably 2 500 μm² to 50 000 μm². Still, otherembodiments are feasible. The expression matrix generally refers to anarrangement of a plurality of the pixels in space, which may be a lineararrangement or an areal arrangement. Thus, generally, the matrixpreferably may be selected from the group consisting of aone-dimensional matrix and a two-dimensional matrix. As an example, thematrix may comprise 100 to 100 000 000 pixels, preferably 1 000 to 1 000000 pixels and, more preferably, 10 000 to 500 000 pixels. Mostpreferably, the matrix is a rectangular matrix having pixels arranged inrows and columns.

As further used herein, the term evaluation device generally refers toan arbitrary device adapted to perform the named operations, preferablyby using at least one data processing device and, more preferably, byusing at least one processor. Thus, as an example, the at least oneevaluation device may comprise at least one data processing devicehaving a software code stored thereon comprising a number of computercommands.

The optical sensor may be adapted to generate at least one signalindicating an intensity of illumination for each of the pixels. Thus, asan example, the optical sensor may be adapted to generate at least oneelectronic signal for each of the pixels, each signal indicating theintensity of illumination for the respective pixel. This signal, in thefollowing, is also referred to as the intensity of the pixel and/or asthe pixel intensity. The signal may be an analogue and/or a digitalsignal. Further, the detector may comprise one or more signal processingdevices, such as one or more filters and/or analogue-digital-convertersfor processing and/or preprocessing the at least one signal.

As further used herein, an intensity distribution generally refers to aplurality or entity of intensity values or items of intensityinformation for a plurality of local positions at which the respectiveintensity value is measured by the optical sensor, such as by the pixelsof the optical sensor. Thus, as an example, an intensity distributionmay comprise a matrix of intensity values or items of intensityinformation, wherein a position of the intensity values or items ofintensity information within the matrix refers to a local position onthe optical sensor. The intensity distribution specifically may compriseintensity values as a function of a transversal position of therespective pixel in a plane perpendicular to an optical axis of theoptical sensor. Additionally or alternatively, the intensitydistribution may comprise intensity values as a function of a pixelcoordinate of the pixels of the matrix. Again, additionally oralternatively, the intensity distribution may comprise a distribution ofa number # of pixels having a specific intensity as a function of theintensity.

As further used herein, a determination of at least one longitudinalcoordinate of the object by using the intensity distribution generallyrefers to the fact that the intensity distribution is evaluated in orderto determine the longitudinal position of the object. As an example, theevaluation device may be adapted to determine the longitudinalcoordinate of the object by using a predetermined relationship betweenthe intensity distribution and the longitudinal coordinate. Thepredetermined relationship may be stored in a data storage of theevaluation device, such as in a lookup table. Additionally oralternatively, empirical evaluation functions may be used forpredetermined relationships between the intensity distribution and thelongitudinal coordinate.

The intensity distribution generally may approximate an intensitydistribution of an illumination by a Gaussian light beam. Otherintensity distributions, however, are possible, specifically in caseNon-Gaussian light beams are used.

For determining the at least one longitudinal coordinate of the object,the evaluation device may simply use a predetermined relationshipbetween the intensity distribution and the longitudinal coordinateand/or may apply one or more evaluation algorithms. Specifically, theevaluation device may be adapted to determine at least one intensitydistribution function approximating the intensity distribution. As usedherein, an intensity distribution function generally is a mathematicalfunction, such as a two-dimensional function f(x) or a three-dimensionalfunction f(x, y), which approximates the actual intensity distributionof the at least one optical sensor and/or a part thereof. Thus, theintensity distribution function may be a fit function derived byapplying one or more well-known fitting or approximation algorithms,such as a regression analysis like least squares fit or others. Thesefitting algorithms generally are known to the skilled person. As anexample, one or more predetermined fitting functions may be given, withone or more parameters, wherein the parameter is chosen such that a bestfit to the intensity distribution is achieved.

As outlined above, the intensity distribution function may approximatethe full intensity distribution or a part thereof. Thus, as an example,a region of the matrix may be used and evaluated for determining theintensity distribution function, such as a three-dimensional intensitydistribution function f(x, y). Additionally or alternatively, atwo-dimensional intensity distribution function f(x) may be used, suchas along an axis or line through the matrix. As an example, a center ofillumination by the light beam may be determined, such as by determiningthe at least one pixel having the highest illumination, and across-sectional axis may be chosen through the center of illumination.The intensity distribution function may be a function of a coordinatealong this cross-sectional axis through the center of illumination,thereby deriving a two-dimensional intensity distribution function.Other evaluation algorithms are feasible.

As outlined above, the evaluation device is adapted to determine thelongitudinal coordinate of the object by using a predeterminedrelationship between a longitudinal coordinate and the intensitydistribution function. Additionally or alternatively, specifically incase one or more intensity distribution functions are fitted to theactual intensity distribution, at least one parameter derived from theintensity distribution function may be determined, and the longitudinalcoordinate of the object may be determined by using a predeterminedrelationship between the at least one parameter, such as the at leastone fit parameter, and the longitudinal coordinate of the object, suchas the distance between the object and the detector.

Further embodiments relate to the nature of the at least one intensitydistribution function. Specifically, the intensity distribution functionmay be a function describing a shape of the at least one light beam, inthe following also referred to as a beam shape. Thus, generally, theintensity distribution function may be or may comprise a beam shapefunction of the light beam. As used herein, a beam shape functiongenerally refers to a mathematical function describing a spatialdistribution of an electric field and/or of an intensity of a lightbeam. As an example, a beam shape function may be a function describingan intensity of a light beam in a plane perpendicular to an axis ofpropagation of the light beam, wherein, optionally, a position along theaxis of propagation may be an additional coordinate. Therein, generally,arbitrary types of coordinate systems may be used for describing thespatial distribution of the electric field and/or the intensity.Preferably, however, a coordinate system is used which comprisesposition in a plane perpendicular to an optical axis of the detector.

As outlined above, the intensity distribution function comprises atwo-dimensional or a three-dimensional mathematical functionapproximating an intensity information contained within at least part ofthe pixels of the optical sensor. Thus, as further outlined above, oneor more fitting algorithms may be used for determining the at least oneintensity distribution function, preferably in at least one planeparallel to the at least one optical sensor. The two-dimensional orthree-dimensional mathematical function specifically may be a functionof at least one pixel coordinate of the matrix of pixels. Additionallyor alternatively, as outlined above, other coordinates may be used, suchas one or more coordinates along one or more lines or axes in a plane ofthe at least one optical sensor, such as along a cross-sectional linethrough a maximum of intensity of the light beam on the at least oneoptical sensor. Thus, specifically, the at least one intensitydistribution function may be a cross-sectional intensity distributionfunction describing an intensity distribution through a center ofillumination.

When using one or more mathematical functions, a pixel position of thepixels of the matrix specifically may be defined by (x, y), with x, ybeing pixel coordinates. Additionally or alternatively, circular orspherical coordinates may be used, such as coordinates with r being adistance from a central point or axis. The latter specifically may beuseful for circular-symmetric intensity distributions as is typicallythe case for e.g. Gaussian light beams illuminating a surfaceperpendicular to an axis of propagation of the light beams (see e.g.equation (2) below). The two-dimensional or three-dimensionalmathematical function specifically may comprise one or more functionsselected from the group consisting of f(x), f(y), f(x, y). As outlinedabove, however, the coordinate systems may be used with one or morecoordinates x′ and/or y′, preferably in a plane of the matrix. Thus, asoutlined above, a coordinate x′ may be chosen on an axis crossing acenter of illumination of the matrix by the light beam. Thereby, anintensity distribution function f(x′) may be derived, describing orapproximating a cross-sectional intensity distribution through thecenter of illumination.

As outlined above, the intensity distribution function generally may bean arbitrary function which typically occurs when a surface isilluminated by a light beam, such as a Gaussian light beam. Therein, oneor more fitting parameters may be used for fitting the function to theactual illumination or intensity distribution. As an example, forGaussian functions as will be explained in further detail below (seee.g. equation (2) below), the width w₀ and/or the longitudinalcoordinate z may be appropriate fitting parameters.

The two-dimensional or three-dimensional mathematical functionspecifically selected from the group consisting of: a bell-shapedfunction; a Gaussian distribution function; a Bessel function; aHermite-Gaussian function; a Laguerre-Gaussian function; a Lorentzdistribution function; a binomial distribution function; a Poissondistribution function. Combinations of these and/or other intensitydistribution functions may be possible.

The above-mentioned intensity distribution may be determined in oneplane or in a plurality of planes. Thus, as outlined above, the detectormay comprise one optical sensor, such as one optical sensor defining asensor plane, only. Alternatively, the detector may comprise a pluralityof optical sensors, such as a sensor stack comprising a plurality ofoptical sensors, each optical sensor defining a sensor plane.Consequently, the detector may be adapted to determine the intensitydistribution in one plane, such as the sensor plane of the singleoptical sensor, or, alternatively, to determine the intensitydistribution in a plurality of planes, such as in a plurality ofparallel planes. As an example, the detector may be adapted to determineat least one intensity distribution per plane, such as for each sensorplane. In case the detector is adapted to determine intensitydistributions in a plurality of planes, the planes specifically may beperpendicular to the optical axis of the detector. The planes may bedetermined by optical sensors, such as by sensor planes of the opticalsensors, such as by sensor planes of the optical sensors of a sensorstack. Thereby, specifically by using a sensor stack, the detector maybe adapted to determine a plurality of intensity distributions fordifferent longitudinal positions along an optical axis of the detector.

In case a plurality of optical sensors is used, specifically a stack ofoptical sensors, the optical sensors preferably are fully or partiallytransparent, as will be outlined in further detail below. Thus, thelight beam preferably may be transmitted through the optical sensors ofthe stack or at least through one or more of the optical sensors of thestack, such that the intensity distributions may be measured for atleast two sensor planes of the optical sensors. Other embodiments,however, are feasible.

In case the detector is adapted to determine intensity distributions fora plurality of planes perpendicular to the optical axis, the evaluationdevice specifically may be adapted to evaluate changes in the intensitydistributions or may be adapted to compare the intensity distributionswith each other and/or with a common standard. Consequently, theevaluation device, as an example, may be adapted to evaluate changes inthe intensity distribution as a function of a longitudinal coordinatealong the optical axis. As an example, the intensity distributions maychange when the light beam propagates along the optical axis. Theevaluation device specifically may be adapted to evaluate a change inthe intensity distribution as a function of a longitudinal coordinatealong the optical axis for determining the longitudinal coordinate ofthe object. Thus, as an example, for Gaussian light beams, the width ofthe light beam changes with propagation, as is evident to the skilledperson, and as shown in equation (3) below. By evaluating changes in theintensity distribution, the width of the light beam and changes of thewidth of the light beam may be determined, thereby allowing fordetermining a focal point of the light beam and thereby allowing fordetermining a longitudinal coordinate of the object from which the lightbeam propagates towards the detector.

In case intensity distributions are determined in a plurality of planes,intensity distribution functions may be derived for one, more than oneor even all of the planes. For potential embodiments of derivingintensity distribution functions, specifically beam shape functions,reference may be made to the embodiments given above. Specifically, theevaluation device may be adapted to determine a plurality of intensitydistribution functions, such as one or more than one intensitydistribution function per intensity distribution, wherein each intensitydistribution function approximates the intensity distribution in one ofthe planes. The evaluation device may further be adapted to derive thelongitudinal coordinate of the object from the plurality of intensitydistribution functions. Therein, again, a predetermined relationshipbetween the intensity distribution functions and the longitudinalcoordinate of the object may be used, such as a simple lookup table.Additionally or alternatively, a dependency of at least one parameter ofthe intensity distribution functions on the position of the opticalsensor along an optical axis and/or a longitudinal position may bedetermined, such as a change of the beam waist or beam diameter when thelight beam travels along the optical axis. Thereof, such as by usingequation (3) below, the focal position of the light beam may be derivedand, thus, information on the longitudinal coordinate of the object maybe gained.

As outlined above, in case a plurality of intensity distributionfunctions is determined, the intensity distribution functionspecifically may be beam shape functions. Specifically, the same type ofbeam shape function may be used and/or may be fitted to each of theintensity distributions. The fitting parameters or parameters maycontain valuable information on the position of the object.

As outlined above, the evaluation device specifically may be adapted toevaluate the intensity distribution functions. Specifically, theevaluation device may be adapted to derive at least one beam parameterfrom each intensity distribution function. Thus, as an example, a centerof intensity may be derived. Additionally or alternatively, a beamwidth, a beam waist or beam diameter may be derived, such as a Gaussianbeam waist according to equation (3) below. As outlined above and aswill be outlined in further detail below, the beam waist may be used fordetermining a longitudinal coordinate. The evaluation devicespecifically may be adapted to evaluate a change of the at least onebeam parameter as a function of a longitudinal coordinate along theoptical axis for determining the longitudinal coordinate of the object.Additionally, as will be outlined in further detail below, a transversalposition may be derived, such as at least one transversal coordinate,such as by evaluating at least one parameter derived by evaluating theintensity distribution function, specifically the beam shape functions.Thus, as an example, the above-mentioned center of illumination mayprovide valuable information on a transversal position of the object,such as by providing at least one transversal coordinate. By trackingthe positions of the centers of illumination for a stack of opticalsensors, a beam tracing may be performed, thereby allowing fordetermining a transversal position, such as one or more than onetransversal coordinate of the object.

The above-mentioned at least one beam parameter which may be derivedfrom the plurality of beam shape functions, such as in a plurality ofplanes perpendicular to an optical axis of the detector, generally maybe an arbitrary beam parameter or combination of beam parameters.Specifically, the at least one beam parameter may be selected from thegroup consisting of: a beam diameter; a beam waist; a Gaussian beamparameter. Additionally or alternatively, as outlined above, a center ofillumination may be determined.

As outlined above, the evaluation device specifically may be adapted todetermine the longitudinal coordinate of the object by using apredetermined relationship between the beam parameters and thelongitudinal coordinate. The predetermined relationship may be or maycomprise an analytical relationship such as the known propagationproperties of a Gaussian light beam, such as given in formulae (2) or(3) below. Additionally or alternatively, other types of predeterminedrelationships may be used, such as empirical or semi-empiricalrelationships. Again, additionally or alternatively, the predeterminedrelationship may be provided as a lookup table, indicating the at leastone longitudinal coordinate as a function of the at least one parameter.Various types of evaluation routines are possible and may easily beimplemented within the evaluation device.

By evaluating intensity distributions in a plurality of planes, thedetector may be adapted to record an image stack, i.e. a stack ofintensity values of pixels matrices in a plurality of planes. The imagestack may be recorded as a three-dimensional matrix of pixels. Byevaluating intensity distribution functions in a plurality of planes,such as by deriving intensity distribution functions in a plurality ofplanes, various types of image evaluation are feasible. Specifically, athree-dimensional image of a light field of the light beam may bederived and/or recorded. Thus, specifically by using pixelated opticalsensors such as pixelated transparent or semitransparent organic opticalsensors as outlined in further detail below, the detector may be adaptedto record a picture stack at different longitudinal positions along anoptical axis, such as at different distances to a lens or lens system ofthe detector. In case a plurality of images is recorded by using a stackof optical sensors, the recording may take place in a serial fashion orsimultaneously.

The picture stack, as outlined above, may be analyzed to obtain3D-information. In order to analyze the picture stack, the detector andspecifically the evaluation device may be adapted to fit beam shapefunctions to model the illumination of the pixels, such as to model theintensity distributions within the pictures of the picture stack. Thebeam shape functions may be compared among the pictures of the picturestack in order to obtain information regarding the light beam and,thereby, in order to obtain information on the longitudinal position ofthe object and, optionally, on a transversal position of the object. Asan example and as outlined above, a broadening or focusing of the lightbeam may be determined, such as by evaluating a beam width or a beamwaist as a function of a longitudinal coordinate along an optical axis,such as as a function of distance from the lens. Focusing or defocusingproperties of the lens or other elements of a transfer device of thedetector may be taken into account, as generally known to the skilledperson in the field of optics. Thus, as an example, in case lensproperties are known and in case a broadening or focusing of the lightbeam is determined by evaluating the intensity distribution functionsmust specifically the beam shape functions, the distance of the objectfrom which the light beam propagates towards the detector may bedetermined, such as by calculation or by using known all predeterminedrelationships.

The evaluation of the intensity distribution in one plane for theevaluation of the intensity distributions in a plurality of planes maybe performed in various ways. Thus, as outlined above, various types ofintensity distribution functions may be used. As an example, therotational-symmetric intensity distribution functions may be used whichare rotationally symmetric about a center of illumination on the plane.Additionally or alternatively, one or more intensity distributionfunctions having other types of symmetry may be used such as lowerdegrees of symmetry. Further, one or more point-symmetric and/ormirror-symmetric intensity distribution functions may be used. Further,combinations of two or more intensity distribution functions may beused, such as combinations of one or more Gaussian functions and one ormore polynomials. Further, derivatives of rotationally symmetricfunctions may be used, and/or products of several functions. Further, atleast one intensity distribution function may be used which is a linearcombination of two or more functions, such as a linear combination oftwo or more Gaussian functions having different exponents. Other typesof intensity distribution functions may be used. Therein, intensitiesmay be evaluated in various ways. An efficient way of analyzing theintensity distributions, also referred to as images, may be an analysisof edges within the intensity distributions. The analysis of edgeswithin intensity distributions may be performed in addition oralternatively to evaluating beam shapes. Still, the analysis of edgesmay be preferable, since the analysis of edges generally allows fordeducing longitudinal coordinates for objects with little or nostructure or contrast. Thus, generally, the detector and the evaluationdevice may be adapted to determine edges within the at least oneintensity distribution or within the plurality of intensitydistributions in a plurality of planes, also referred to as the imagestack. The development of edges and/or a comparison of the edges withinthe images of the image stack may allow for deriving an item oflongitudinal position information of the object.

The evaluation device further may be adapted to compare, for each of thepixels, the signal to at least one threshold in order to determinewhether the pixel is an illuminated pixel or not. This at least onethreshold may be an individual threshold for each of the pixels or maybe a threshold which is a uniform threshold for the whole matrix. Incase a plurality of optical sensors is provided, at least one thresholdmay be provided for each of the optical sensors and/or for a groupcomprising at least two of the optical sensors, wherein, for two opticalsensors, their respective thresholds may be identical or different.Thus, for each of the optical sensors, an individual threshold may beprovided.

As will be outlined in further detail below, the threshold may bepredetermined and/or fixed. Alternatively, the at least one thresholdmay be variable. Thus, the at least one threshold may be determinedindividually for each measurement or groups of measurements. Thus, atleast one algorithm may be provided adapted to determine the threshold.

The evaluation device generally may be adapted to determine at least onepixel having the highest illumination out of the pixels by comparing thesignals of the pixels. Thus, the detector generally may be adapted todetermine one or more pixels and/or an area or region of the matrixhaving the highest intensity of the illumination by the light beam. Asan example, in this way, a center of illumination by the light beam maybe determined.

The highest illumination and/or the information about the at least onearea or region of highest illumination may be used in various ways.Thus, as outlined above, the at least one above-mentioned threshold maybe a variable threshold. As an example, the evaluation device may beadapted to choose the above-mentioned at least one threshold as afraction of the signal of the at least one pixel having the highestillumination. Thus, the evaluation device may be adapted to choose thethreshold by multiplying the signal of the at least one pixel having thehighest illumination with a factor of 1/e^(z). As will be outlined infurther detail below, this option is particularly preferred in caseGaussian propagation properties are assumed for the at least one lightbeam, since the threshold 1/e² generally determines the borders of alight spot having a beam radius or beam waist w generated by a Gaussianlight beam on the optical sensor.

In a further embodiment of the present invention, which may also becombined with one or more of the above-mentioned embodiments and/or withone or more of the further options disclosed in further detail below,the determining of the intensity distribution may comprise determining anumber N of pixels of the optical sensor which are illuminated by thelight beam, wherein the determining of the at least one longitudinalcoordinate of the object comprises using the number N of pixels whichare illuminated by the light beam.

As used herein, the term “determining a number N of pixels of theoptical sensor which are illuminated by the light beam” generally refersto a process of quantitatively evaluating the pixels of the opticalsensor, thereby generating at least one numerical value which, herein,is denoted by “N”. Therein, N generally may refer to a single numericalvalue, such as a single integer value. This embodiment, as an example,may be implemented by simply subdividing the pixels into illuminatedpixels and non-illuminated pixels, wherein N may simply be referred toas the number of pixels in the sub-class of illuminated pixels.

Additionally or alternatively, the pixels may be subdivided into morethan two classes or sub-classes, such as into subclasses according toone or more of their position, their illumination or degree ofillumination. Thus, as an example, the evaluation device may be adaptedto determine an intensity distribution over at least part of the pixelswhich are illuminated by the light beam. In other words, the evaluationdevice may be adapted to subdivide the totality of pixels or a partthereof, such as the illuminated pixels, into a plurality of classesaccording to their illumination and/or position. Thus, as an example,the evaluation device may be adapted to subdivide the totality of pixelsor a part thereof into subclasses, based e.g. on a picture analysisalgorithm such as edge or shape detection or on a separation intoregions with similar contrast, saturation, hue, etc. Other algorithmsfor subdividing the totality of pixels into two or more subclasses arepossible.

The evaluation device may be adapted to determine the longitudinalcoordinate of the object by using a predetermined relationship betweenthe number N of the pixels which are illuminated by the light beam andthe longitudinal coordinate of the object. Thus, generally, the diameterof the light beam, due to propagation properties generally known to theskilled person, changes with propagation, such as with a longitudinalcoordinate of the propagation. The relationship between the number ofilluminated pixels and the longitudinal coordinate of the object may bean empirically determined relationship and/or may be analyticallydetermined. Thus, as an example, a calibration process may be used fordetermining the relationship between the number of illuminated pixelsand the longitudinal coordinate. Additionally or alternatively, asmentioned above, the predetermined relationship may be based on theassumption of the light beam being a Gaussian light beam. The light beammay be a monochromatic light beam having a precisely one wavelength λ ormay be a light beam having a plurality of wavelengths or a wavelengthspectrum, wherein, as an example, a central wavelength of the spectrumand/or a wavelength of a characteristic peak of the spectrum may bechosen as the wavelength λ of the light beam. In case a plurality ofoptical sensors is used, specific predetermined relationships betweenthe respective number of illuminated pixels of the optical sensors andthe longitudinal coordinate may be used. Thus, as an example, for eachoptical sensor, a predetermined relationship between the number ofilluminated pixels and the longitudinal coordinate may be provided. Aswill be outlined in further detail below, the optical sensors may bearranged in a stack. Further, the optical sensors may have differentproperties, such as different geometries such as different geometries ofthe matrix of pixels and/or of the pixels. Further, the optical sensorsmay have differing sensitivities, such as differing spectralsensitivities. By providing specific predetermined relationships betweenthe respective numbers of illuminated pixels of the optical sensors,these differing properties of the optical sensors may be taken intoaccount.

As an example of an analytically determined relationship, thepredetermined relationship, which may be derived by assuming Gaussianproperties of the light beam, may be:

$\begin{matrix}{{N \sim {\pi \cdot w_{0}^{2} \cdot \left( {1 + \left( \frac{z}{z_{0}} \right)^{2}} \right)}},} & (1)\end{matrix}$

wherein z is the longitudinal coordinate,

wherein w₀ is a minimum beam radius of the light beam when propagatingin space,

wherein z₀ is a Rayleigh-length of the light beam with z₀=π·w₀ ²/λ, λbeing the wavelength of the light beam.

In case N is an integer number, formula (1) may imply the formation ofinteger numbers, such as by using additional functions like functionsfinding the closest integer number, such as the closest integer numberbeing smaller or equal or greater or equal than the term on the righthand side of formula (1). Other integer formation functions arefeasible.

This relationship may generally be derived from the general equation ofan intensity I of a Gaussian light beam traveling along a z-axis of acoordinate system, with r being a coordinate perpendicular to the z-axisand E being the electric field of the light beam:I(r,z)=|E(r,z)|² =I ₀·(w ₀ /w(z))² ·e ^(−2r) ² ^(/w(z)) ²   (2)

The beam radius w of the transversal profile of the Gaussian light beamgenerally representing a Gaussian curve is defined, for a specificz-value, as a specific distance from the z-axis at which the amplitude Ehas dropped to a value of 1/e (approx. 36%) and at which the intensity Ihas dropped to 1/e^(z). The minimum beam radius, which, in the Gaussianequation given above (which may also occur at other z-values, such aswhen performing a z-coordinate transformation), occurs at coordinatez=0, is denoted by w₀. Depending on the z-coordinate, the beam radiusgenerally follows the following equation when light beam propagatesalong the z-axis:

$\begin{matrix}{{w(z)} = {w_{0} \cdot \sqrt{1 + \left( \frac{z}{z_{0}} \right)^{2}}}} & (3)\end{matrix}$

With the number N of illuminated pixels being proportional to theilluminated area A of the optical sensor:N˜A  (4)

or, in case a plurality of optical sensors i=1, . . . , n is used, withthe number N_(i) of illuminated pixels for each optical sensor beingproportional to the illuminated area A_(i) of the respective opticalsensorN _(i) ˜A _(i)  (4′)

and the general area of a circle having a radius w:A=π·w ²,  (5)

the following relationship between the number of illuminated pixels andthe z-coordinate may be derived:

$\begin{matrix}{{N \sim {\pi \cdot w_{0}^{2} \cdot \left( {1 + \left( \frac{z}{z_{0}} \right)^{2}} \right)}}{or}} & (6) \\{{N_{i} \sim {\pi \cdot w_{0}^{2} \cdot \left( {1 + \left( \frac{z}{z_{0}} \right)^{2}} \right)}},} & \left( 6^{\prime} \right)\end{matrix}$

respectively, with z₀=π·w₀ ²/λ, as mentioned above. Thus, with N orN_(i), respectively, being the number of pixels within a circle beingilluminated at an intensity o I≥I₀/e², as an example, N or N_(i) may bedetermined by simple counting of pixels and/or other methods, such as ahistogram analysis. In other words, a well-defined relationship betweenthe z-coordinate and the number of illuminated pixels N or N_(i),respectively, may be used for determining the longitudinal coordinate zof the object and/or of at least one point of the object, such as atleast one longitudinal coordinate of at least one beacon device beingone of integrated into the object and/or attached to the object.

As outlined above, the above-mentioned functions such as given inequations (2) or (3) may also be used as a beam shape functions orintensity distribution functions for approximating an intensitydistribution in one or more planes, specifically in one or more planesperpendicular to an optical axis of the detector.

The invention, as outlined above, is generally based on determining atleast one longitudinal coordinate of the object by using an intensitydistribution which may be approximated by one or more intensitydistribution functions, such as by using the above-mentioned fittingprocess of fitting one or more beam shape functions to the intensitydistribution and/or by using the above-mentioned process of determiningthe number N of pixels of the optical sensor which are illuminated bythe light beam. In the equations given above, such as in equations (1),(2) or (3), it is assumed that the light beam has a focus at positionz=0. It shall be noted however, that a coordinate transformation of thez-coordinate is possible, such as by adding and/or subtracting aspecific value. Thus, as an example, the position of the focus typicallyis dependent on the distance of the object from the detector and/or onother properties of the light beam. Thus, by determining the focusand/or the position of the focus, a position of the object, specificallya longitudinal coordinate of the object, may be determined, such as byusing an empirical and/or an analytical relationship between a positionof the focus and a longitudinal coordinate of the object and/or thebeacon device. Further, imaging properties of the at least one optionaltransfer device, such as the at least one optional lens, may be takeninto account. Thus, as an example, in case beam properties of the lightbeam being directed from the object towards the detector are known, suchas in case emission properties of an illuminating device contained in abeacon device are known, by using appropriate Gaussian transfer matricesrepresenting a propagation from the object to the transfer device,representing imaging of the transfer device and representing beampropagation from the transfer device to the at least one optical sensor,a correlation between a beam waist and a position of the object and/orthe beacon device may easily be determined analytically. Additionally oralternatively, a correlation may empirically be determined byappropriate calibration measurements.

As outlined above, the matrix of pixels preferably may be atwo-dimensional matrix. However, other embodiments are feasible, such asone-dimensional matrices. More preferably, as outlined above, the matrixof pixels is a rectangular matrix.

The detector may comprise precisely one optical sensor or may comprise aplurality of the optical sensors. In case a plurality of the opticalsensors is provided, the optical sensors may arrange in various ways.Thus, as an example, the light beam may be split into two or more beams,each beam being directed towards one or more of the optical sensors.Additionally or alternatively, two or more of the optical sensors may bestacked along an axis, such as along an optical axis of the detector,preferably with their sensitive areas face towards the same direction.Thus, as an example, the detector may comprise a plurality of theoptical sensors, wherein the optical sensors are stacked along anoptical axis of the detector.

As an example, the detector may comprise n optical sensors, with n>1.Therein, preferably, n is a positive integer. As outlined above, theintensity distribution may be evaluated in the sensor planes of the noptical sensors, such as by deriving intensity distribution functionsfor each of the sensor planes. Additionally or alternatively, theevaluation device generally may be adapted to determine the number N_(i)of the pixels which are illuminated by the light beam for each of theoptical sensors, wherein i∈{1,n} denotes the respective optical sensor.As used herein, “each” refers to the fact that a number of illuminatedpixels is determined for each optical sensor part of a plurality of theoptical sensors, notwithstanding the fact that optical sensors may existwhich are not illuminated by the light beam and/or which are used forother purposes, and, consequently, for which no number of illuminatedpixels is determined.

The evaluation device may be adapted to compare the number N_(i) ofpixels which are illuminated by the light beam for each optical sensorwith at least one neighboring optical sensor, thereby resolving anambiguity in the longitudinal coordinate of the object.

The sensor signals of the optical sensors may be used in various ways.Thus, as an example, the redundancy of the sensor signals may be usedfor eliminating unknown information regarding the power of the lightbeam. Thus, the sensor signals may be normalized, such as by setting thestrongest sensor signal to value 1 or 100 and providing the remainingsensor signals as fractions of this strongest sensor signal. Thus,generally, the evaluation device may be adapted to normalize sensorsignals of the optical sensors for a power of the light beam.Additionally or alternatively, however, as outlined above, anormalization may take place within each optical sensor, such as forsetting appropriate thresholds for determining pixels which areilluminated by the light beam and for determining pixels which are notilluminated by the light beam.

The at least one optical sensor generally may be transparent or may beintransparent. Thus, as an example, the optical sensor may betransparent and adapted to transmit at least 10%, preferably at least20% and, more preferably, at least 50% of the power of the light beam.In case a plurality of the optical sensors is provided, such as in astacked fashion, preferably, at least one of the optical sensors istransparent.

In case a plurality of the optical sensors is provided, which may bearranged in the stacked fashion and/or in another arrangement, theoptical sensors may have identical spectral sensitivities or may providedifferent spectral sensitivities. Thus, as an example, at least two ofthe optical sensors may have a differing spectral sensitivity. As usedherein, the term spectral sensitivity generally refers to the fact thatthe sensor signal of the optical sensor, for the same power of the lightbeam, may vary with the wavelength of the light beam. Thus, generally,at least two of the optical sensors may differ with regard to theirspectral properties. This embodiment generally may be achieved by usingdifferent types of absorbing materials for the optical sensors, such asdifferent types of dyes or other absorbing materials. Additionally oralternatively, differing spectral properties of the optical sensors maybe generated by other means implemented into the optical sensors and/orinto the detector, such as by using one or more wavelength-selectiveelements, such as one or more filters (such as color filters) in frontof the optical sensors and/or by using one or more prisms and/or byusing one or more dichroitic mirrors. Thus, in case a plurality ofoptical sensors is provided, at least one of the optical sensors maycomprise a wavelength-selective element such as a color filter, having aspecific transmission or reflection characteristic, thereby generatingdiffering spectral properties of the optical sensors. Further, as willbe outlined in further detail below, in case a plurality of opticalsensors is used, these optical sensors may all be organic opticalsensors, may all be inorganic optical sensors, may all be hybridorganic-inorganic optical sensors or may comprise an arbitrarycombination of at least two optical sensors selected from the groupconsisting of organic optical sensors, inorganic optical sensors andhybrid organic-inorganic optical sensors.

In case a plurality of the optical sensors is used, wherein at least twoof the optical sensors differ with regard to their respective spectralsensitivity, the evaluation device generally may be adapted to determinea color of the light beam by comparing sensor signals of the opticalsensors having the differing spectral sensitivity. As used herein, theexpression “determine a color” generally refers to the step ofgenerating at least one item of spectral information about the lightbeam. The at least one item of spectral information may be selected fromthe group consisting of a wavelength, specifically a peak wavelength;color coordinates, such as CIE coordinates.

The determination of the color of the light beam may be performed invarious ways which are generally known to the skilled person. Thus, thespectral sensitivities of the optical sensors may span a coordinatesystem in color space, and the signals provided by the optical sensorsmay provide a coordinate in this color space, as known to the skilledperson for example from the way of determining CIE coordinates.

As an example, the detector may comprise two, three or more opticalsensors in a stack. Thereof, at least two, preferably at least three, ofthe optical sensors may have differing spectral sensitivities. Further,the evaluation device may be adapted to generate at least one item ofcolor information for the light beam by evaluating the signals of theoptical sensors having differing spectral sensitivities.

As an example, at least three optical sensors being spectrally sensitiveoptical sensors may be contained in the stack. Thus, e.g., thespectrally sensitive optical sensors may comprise at least one redsensitive optical sensor, the red sensitive optical sensor having amaximum absorption wavelength λr in a spectral range 600 nm<λr<780 nm,wherein the spectrally sensitive optical sensors further comprise atleast one green sensitive optical sensor, the green sensitive opticalsensor having a maximum absorption wavelength λg in a spectral range 490nm<λg<600 nm, wherein the spectrally sensitive optical sensors furthermay comprise at least one blue sensitive optical sensor, the bluesensitive optical sensor having a maximum absorption wavelength λb in aspectral range 380 nm<λb<490 nm. As an example, the red sensitiveoptical sensor, the green sensitive optical sensor and the bluesensitive optical sensor, in this order or in a different order, may bethe first optical sensors of the optical sensor stack, facing towardsthe object.

The evaluation device may be adapted to generate at least two colorcoordinates, preferably at least three color coordinates, wherein eachof the color coordinates is determined by dividing a signal of one ofthe spectrally sensitive optical sensors by a normalization value. As anexample, the normalization value may contain a sum of the signals of allspectrally sensitive optical sensors. Additionally or alternatively, thenormalization value may contain a detector signal of a white detector.

The at least one item of color information may contain the colorcoordinates. The at least one item of color information may, as anexample, contain CIE coordinates.

In addition to the preferred at least two, more preferably at leastthree, spectrally sensitive optical sensors, the stack further maycomprise at least one white detector, wherein the white detector may beadapted to absorb light in an absorption range of all spectrallysensitive detectors. Thus, as an example, the white detector may have anabsorption spectrum absorbing light all over the visible spectral range.

The spectrally sensitive optical sensors each may comprise at least onedye, the dye being adapted to absorb light in one or more of the visiblespectral range, the ultraviolet spectral range and the infrared spectralrange, with a non-uniform absorption spectrum. As an example, the dyeseach may have an absorption spectrum having at least one absorptionpeak. The absorption peak, as a solid, as a film or as sensitizer on ascaffold material (e.g. TiO₂), may have a width, such as a full width athalf maximum (FWHM) which may be broad, such as by using dyes absorbingall over one or more of the visible, the infrared or the ultravioletspectral range, or may be narrow, such as by using dyes having an FWHMof no more than 300 nm, preferably of no more than 200 nm, morepreferably of no more than 80 nm, of no more than 60 nm or of no morethan 40 nm. The absorption peaks of the dyes may be spaced apart by atleast 60 nm, preferably at least 80 nm and, more preferably, by at least100 nm. Other embodiments are feasible.

In case the detector comprises a plurality of optical sensors, asoutlined above, the optical sensors preferably may be arranged in astack. In case a plurality of optical sensors is provided, the opticalsensors may be identical, or at least two of the optical sensors maydiffer with regard to at least one property, such as with regard to ageometric property, a property of device setup or, as outlined above,spectral sensitivity.

As an example, as outlined above, the plurality of optical sensors mayprovide differing spectral sensitivities, such as an optical sensor withsensitivity in the red spectral range (R), an optical sensor withspectral sensitivity in the green spectral range (G) and an opticalsensor with spectral sensitivity in the blue spectral range (B). Asoutlined above, the differing spectral sensitivities may be provided byvarious means, such as by providing absorbing materials having differingspectral sensitivities and/or by providing one or morewavelength-selective elements. Thus, in a stack of optical sensorsand/or in another arrangement of a plurality of optical sensors, variouscombinations of optical sensors having differing spectral sensitivitiesmay be provided. As an example, an RGB stack may be provided, in thegiven order or in a different order. Additionally or alternatively, twooptical sensors having different spectral sensitivities may besufficient to derive color information, such as by evaluating a ratio ofsensor signals of optical sensors having differing spectralsensitivities.

Further, in case a plurality of optical sensors is provided, theplurality of optical sensors may differ with regard to device setupand/or with regard to the materials used in the optical sensors.Specifically, the optical sensors may differ with regard to theirorganic or inorganic in nature. Thus, the plurality of optical sensorsand, more specifically, the stack, may comprise one or more organicoptical sensors, one or more inorganic optical sensors, one or morehybrid organic-inorganic optical sensors or an arbitrary combination ofat least two of these optical sensors. Thus, as an example, the stackmay consist of organic optical sensors only, may consist of inorganicoptical sensors only or may consist of hybrid organic-inorganic opticalsensors, only. Additionally or alternatively, the stack may comprise atleast one organic optical sensor and at least one inorganic opticalsensor or may comprise at least one organic optical sensor and at leastone hybrid organic-inorganic optical sensor or may comprise at least oneorganic optical sensor and at least one hybrid organic-inorganic opticalsensor. Preferably, the stack may comprise at least one organic opticalsensor and, further, preferably on a side of the stack furthest awayfrom the object, at least one inorganic optical sensor. Thus, as anexample, as will be outlined in further detail below, the stack maycomprise at least one organic optical sensor, such as at least one DSCor sDSC, and, further, at least one inorganic sensor such as a CCD orCMOS sensor chip more preferably on a side of the stack furthest awayfrom the object.

Further, in case a plurality of optical sensors is provided, the opticalsensors may differ with regard to their transparency. Thus, as anexample, all optical sensors may fully or partially be transparent.Alternatively, all optical sensors may fully or partially beintransparent (also referred to as opaque). Further, specifically incase the plurality of optical sensors is arranged as a stack, acombination of at least one at least partially transparent opticalsensor and at least one at least partially intransparent optical sensormay be used. Thus, the stack may comprise one or more transparentoptical sensors and, additionally, preferably on a side of the stackfurthest away from the object, at least one intransparent opticalsensor. Thus, as outlined above, one or more at least partiallytransparent optical sensors may be provided by using one or moretransparent organic optical sensors such as one or more transparent DSCsor sDSCs. Additionally or alternatively, at least partially transparentoptical sensors may be provided by using inorganic sensors, such as verythin inorganic optical sensors or inorganic optical sensors having abandgap which is designed such that at least a part of the incidentlight beam is transmitted. Intransparent optical sensors may be providedby using intransparent electrodes and/or intransparent absorbingmaterials, such as organic and/or inorganic materials. As an example, anorganic optical sensor may be provided having a thick metal electrode,such as a metal electrode having a thickness of more than 50 nm,preferably more than 100 nm. Additionally or alternatively, andinorganic optical sensor may be provided having an intransparentsemiconductor material. As an example, typical CCD or CMOS camera chipsprovide intransparent properties. As an example, the stack may compriseone or more at least partially transparent DSCs or sDSCs and, on a sidefurthest away from the object, an intransparent CMOS or CCD chip. Otherembodiments are feasible.

As outlined above, the detector may further comprise at least onetransfer device. The transfer device preferably may be positioned in alight path in between the object and the detector. As used herein, atransfer device generally is an arbitrary optical element adapted toguide the light beam onto the optical sensor. The guiding may take placewith unmodified properties of the light beam or may take place withimaging or modifying properties. Thus, generally, the transfer devicemight have imaging properties and/or beam-shaping properties, i.e. mightchange a beam waist and/or a widening angle of the light beam and/or ashape of the cross-section of the light beam when the light beam passesthe transfer device. The transfer device, as an example, may compriseone or more elements selected from the group consisting of a lens and amirror. The mirror may be selected from the group consisting of a planarmirror, a convex mirror and a concave mirror. Additionally oralternatively, one or more prisms may be comprised. Additionally oralternatively, one or more wavelength-selective elements may becomprised, such as one or more filters, specifically color filters,and/or one or more dichroitic mirrors. Again, additionally oralternatively, the transfer device may comprise one or more diaphragms,such as one or more pinhole diaphragms and/or iris diaphragms.

The transfer device can for example comprise one or a plurality ofmirrors and/or beam splitters and/or beam deflecting elements in orderto influence a direction of the electromagnetic radiation. Alternativelyor additionally, the transfer device can comprise one or a plurality ofimaging elements which can have the effect of a converging lens and/or adiverging lens. By way of example, the optional transfer device can haveone or a plurality of lenses and/or one or a plurality of convex and/orconcave mirrors. Once again alternatively or additionally, the transferdevice can have at least one wavelength-selective element, for exampleat least one optical filter. Once again alternatively or additionally,the transfer device can be designed to impress a predefined beam profileon the electromagnetic radiation, for example, at the location of thesensor region and in particular the sensor area. The above-mentionedoptional embodiments of the optional transfer device can, in principle,be realized individually or in any desired combination. The at least onetransfer device, as an example, may be positioned in front of thedetector, i.e. on a side of the detector facing towards the object.

In addition to the at least one longitudinal coordinate of the object,at least one transversal coordinate of the object may be determined.Thus, generally, the evaluation device may further be adapted todetermine at least one transversal coordinate of the object bydetermining a position of the light beam on the matrix of pixels.Additionally or alternatively, such as by tracking a center ofillumination through a stack of optical sensors, a beam path of thelight beam may be followed, thereby deriving at least one informationregarding a transversal position of the object.

As an example for determining a center of illumination, the evaluationdevice may be adapted to determine a center of illumination of the atleast one matrix by the light beam, wherein the at least one transversalcoordinate of the object is determined by evaluating at least onecoordinate of the center of illumination. Thus, the coordinate of thecenter of illumination may be a pixel coordinate of the center ofillumination. As an example, the matrix may comprise rows and columns ofpixels, wherein the row number of the light beam and/or the center ofthe light beam within the matrix may provide an x-coordinate, andwherein the column number of the light beam and/or the center of thelight beam within the matrix may provide a y-coordinate.

By providing one or more transversal coordinates, such as x- and/ory-coordinates, the evaluation device is adapted to provide at least onethree-dimensional position of the object. Additionally or alternatively,as outlined above, the evaluation device may be adapted to capture athree-dimensional image of a scene. Specifically, the evaluation devicemay be adapted to provide at least one three-dimensional image of ascene captured by the detector.

Further options of the present invention refer to potential embodimentsof the at least one optical sensor. Generally, an arbitrary opticalsensor device having a matrix of pixels used, such as an optical sensordevice selected from the group consisting of: an inorganic semiconductorsensor device such as a CCD chip and/or a CMOS chip; an organicsemiconductor sensor device. In the latter case, as an example, theoptical sensor may, for example, comprise at least one organicphotovoltaic device having a matrix of pixels. As used herein, anorganic photovoltaic device generally refers to a device having at leastone organic photosensitive element and/or at least one organic layer.Therein, generally, any type of organic photovoltaic device may be used,such as organic solar cells and/or an arbitrary device having at leastone organic photosensitive layer. As an example, an organic solar celland/or a dye-sensitized organic solar cell may be comprised. Further, ahybrid device may be used, such as inorganic-organic photovoltaicdevices. The detector may comprise one or more organic photovoltaicdevices and/or may comprise one or more inorganic photovoltaic devicesand/or may comprise a combination consisting of one or more organicphotovoltaic devices and one or more inorganic photovoltaic devices.

The optical sensor specifically may comprise at least one dye-sensitizedsolar cell having at least one patterned electrode. For potentialembodiments of dye-sensitized solar cells, reference may be made to WO2012/110924 A1 and to U.S. provisional applications Nos. 61/739,173 and61/749,964. The device setups of the dye-sensitized solar cellsdisclosed therein, specifically of the optical sensors disclosedtherein, may generally also be applied to the present invention, withthe proviso that at least one of the electrodes of these dye-sensitizedsolar cells is patterned in order to provide a plurality of pixels.Thus, as an example, one or both of the first and second electrodes ofthe dye-sensitized solar cells disclosed in the named documents may bepatterned. As an example, the first electrode may be patterned toprovide a plurality of parallel horizontal stripes, and the secondelectrode may be patterned to provide a plurality of parallel verticalstripes, or vice versa. Thus, at each crossing point of a stripe of thefirst electrode and a stripe of the second electrode, a pixel isprovided which, by electrically contacting the respective stripes of theelectrodes and measuring an electrical current and/or voltage, may beread out.

The optical sensor specifically may comprise at least one firstelectrode, at least one n-semiconducting metal oxide, at least one dye,at least one p-semiconducting organic material, preferably a solidp-semiconducting organic material, and at least one second electrode,with the at least one n-semiconducting metal oxide, the at least one dyeand the at least one p-semiconducting organic material being embedded inbetween the first electrode and the second electrode.

As mentioned above and as will be outlined in further detail below,generally, for potential embodiments of materials or layer combinationswhich may be used for the first electrode, the at least onen-semiconducting metal oxide, the at least one dye, the at least onep-semiconducting organic material and the at least one second electrode,reference may be made to the above-mentioned WO 2012/110924 A1 as wellas to U.S. provisional applications 61/739,173, filed on Dec. 19, 2012,and 61/749,964, filed on Jan. 8, 2013. Still, other embodiments arefeasible. Thus, as an example, the n-semiconducting metal oxide maycomprise a nanoporous layer of a metal oxide and a dense layer of ametal oxide. The metal oxide preferably may be or may comprise titaniumdioxide. For potential dyes, reference may be made to the dyes mentionedin the above-mentioned documents, such as to the dye ID 504. Further,with regard to potential p-semiconducting organic materials, as anexample, spiro-MeOTAD may be used, as disclosed in one or more of theabove-mentioned documents. Similarly, for potential electrode materials,both transparent and intransparent, reference may be made to thesedocuments. As outlined above, other embodiments are feasible.

Both the first electrode and the second electrode may be transparent.However, other electrode setups may be possible.

As outlined above, preferably, at least one of the first electrode andthe second electrode may be a patterned electrode. Thus, as an example,one or both of the first electrode and the second electrode may comprisea plurality of electrode stripes, such as horizontal electrode stripesand/or vertical electrode stripes. As an example for pixelated opticalsensors which may also be used in the context of the present invention,reference may be made to EP patent application No. 13171898.3, the fullcontent of which is herewith included by reference. Still, otherpixelated optical sensors may be used.

As an example, as outlined above, the first electrode may comprise aplurality of electrode stripes and the second electrode may comprise aplurality of electrode stripes, wherein the electrode stripes of thefirst electrode are oriented perpendicular to the electrode stripes ofthe second electrode. As outlined above, at each crossing point ofelectrode stripes of the first electrode and an electrode stripe of thesecond electrode, a pixel is formed which may be read out independently.

The detector may further comprise appropriate reading electronics, suchas a reading electronics adapted to contact one of the electrode stripesof the first electrode and to contact one of the electrode stripes ofthe second electrode and to measure a current through the stripes and/orto measure a voltage at the respective stripes. In order to read out thepixels, a sequential reading scheme may be chosen and/or a multiplexingscheme. Thus, as an example, all pixels within one row may be read outsimultaneously, before switching to the next row of the matrix, therebysequentially reading out all pixel rows. Alternatively, a rowmultiplexing be chosen, reading out all pixels of one columnspontaneously, before switching to the next column. However, otherreadout schemes are possible, such as readout schemes using a pluralityof transistors. Generally, passive matrix and/or active matrix readoutschemes may be used. As an example of read-out schemes which may beused, reference may be made to US 2007/0080925 A1. Other readout schemesare feasible.

For potential electrode materials, reference may be made to WO2012/110924 A1 and to U.S. provisional applications Nos. 61/739,173 and61/749,964. Other embodiments are possible. Specifically, at least oneof the first electrode and the second electrode may comprise anelectrically conductive polymer. Specifically, a transparentelectrically conductive polymer may be used. For potential embodimentsof electrically conductive polymers, reference may be made to the nameddocuments.

It shall be noted, however, that any other type of optical sensors,preferably transparent optical sensors, having a plurality of pixels,may be used for the present invention.

In a further aspect of the present invention, a detector system fordetermining a position of at least one object is disclosed. The detectorsystem comprises at least one detector according to the presentinvention, such as at least one detector as disclosed in one or more ofthe embodiments described above and/or as disclosed in one or more ofthe embodiments disclosed in further detail below.

The detector system further comprises at least one beacon device adaptedto direct at least one light beam towards the detector. As used hereinand as will be disclosed in further detail below, a beacon devicegenerally refers to an arbitrary device adapted to direct at least onelight beam towards the detector. The beacon device may fully orpartially be embodied as an active beacon device, comprising at leastone illumination source for generating the light beam. Additionally oralternatively, the beacon device may fully or partially be embodied as apassive beacon device comprising at least one reflective element adaptedto reflect a primary light beam generated independently from the beacondevice towards the detector.

The beacon device may be at least one of attachable to the object,holdable by the object and integratable into the object. Thus, thebeacon device may be attached to the object by an arbitrary attachmentmeans, such as one or more connecting elements. Additionally oralternatively, the object may be adapted to hold the beacon device, suchas by one or more appropriate holding means. Additionally oralternatively, again, the beacon device may fully or partially beintegrated into the object and, thus, may form part of the object oreven may form the object.

Generally, with regard to potential embodiments of the beacon device,reference may be made to one or more of U.S. provisional applications61/739,173, filed on Dec. 19, 2012, and 61/749,964, filed on Jan. 8,2013. Still, other embodiments are feasible.

As outlined above, the beacon device may fully or partially be embodiedas an active beacon device and may comprise at least one illuminationsource. Thus, as an example, the beacon device may comprise a generallyarbitrary illumination source, such as an illumination source selectedfrom the group consisting of a light-emitting diode (LED), a light bulb,an incandescent lamp and a fluorescent lamp. Other embodiments arefeasible.

Additionally or alternatively, as outlined above, the beacon device mayfully or partially be embodied as a passive beacon device and maycomprise at least one reflective device adapted to reflect a primarylight beam generated by an illumination source independent from theobject. Thus, in addition or alternatively to generating the light beam,the beacon device may be adapted to reflect a primary light beam towardsthe detector.

The detector system may comprise one, two, three or more beacon devices.Thus, generally, in case the object is a rigid object which, at least ona microscope scale, thus not change its shape, preferably, at least twobeacon devices may be used. In case the object is fully or partiallyflexible or is adapted to fully or partially change its shape,preferably, three or more beacon devices may be used. Generally, thenumber of beacon devices may be adapted to the degree of flexibility ofthe object. Preferably, the detector system comprises at least threebeacon devices.

The object generally may be a living or non-living object. The detectorsystem even may comprise the at least one object, the object therebyforming part of the detector system. Preferably, however, the object maymove independently from the detector, in at least one spatial dimension.

The object generally may be an arbitrary object. In one embodiment, theobject may be a rigid object. Other embodiments are feasible, such asembodiments in which the object is a non-rigid object or an object whichmay change its shape.

As will be outlined in further detail below, the present invention mayspecifically be used for tracking positions and/or motions of a person,such as for the purpose of controlling machines, gaming or simulation ofsports. In this or other embodiments, specifically, the object may beselected from the group consisting of: an article of sports equipment,preferably an article selected from the group consisting of a racket, aclub, a bat; an article of clothing; a hat; a shoe.

In a further aspect of the present invention, a human-machine interfacefor exchanging at least one item of information between a user and amachine is disclosed. The human-machine interface comprises at least onedetector system according to the present invention, such as to one ormore of the embodiments disclosed above and/or according to one or moreof the embodiments disclosed in further detail below. The beacon devicesare adapted to be at least one of directly or indirectly attached to theuser and held by the user. The human-machine interface is designed todetermine at least one position of the user by means of the detectorsystem. The human-machine interface further is designed to assign to theposition at least one item of information.

In a further aspect of the present invention, an entertainment devicefor carrying out at least one entertainment function is disclosed. Theentertainment device comprises at least one human-machine interfaceaccording to the present invention. The entertainment device further isdesigned to enable at least one item of information to be input by aplayer by means of the human-machine interface. The entertainment devicefurther is designed to vary the entertainment function in accordancewith the information.

In a further aspect of the present invention, a tracking system fortracking a position of at least one movable object is disclosed. Thetracking system comprises at least one detector system according to thepresent invention, such as to one or more of the embodiments disclosedabove and/or according to one or more of the embodiments disclosed infurther detail below. The tracking system further comprises at least onetrack controller, wherein the track controller is adapted to track aseries of positions of the object at specific points in time.

In a further aspect of the present invention, a method for determining aposition of at least one object is disclosed. The method comprises thefollowing steps, which may be performed in the given order or in adifferent order. Further, two or more or even all of the method stepsmay be performed simultaneously and/or overlapping in time. Further,one, two or more or even all of the method steps may be performedrepeatedly. The method may further comprise additional method steps. Themethod comprises the following method steps:

-   -   at least one detection step, wherein at least one light beam        traveling from the object to a detector is detected by at least        one optical sensor of the detector, the at least one optical        sensor having a matrix of pixels; and    -   at least one evaluation step, wherein an intensity distribution        of pixels of the optical sensor is determined which are        illuminated by the light beam, wherein at least one longitudinal        coordinate of the object is determined by using the intensity        distribution.

The method preferably may be performed by using at least one detectoraccording to the present invention, such as according to one or more ofthe embodiments disclosed above and/or according to one or more of theembodiments disclosed in further detail below. Thus, for preferredoptional embodiments of the method, reference may be made to thedisclosure of the detector or vice a versa. The method may further beperformed by using the detector system, the human-machine interface, theentertainment device or the tracking system according to the presentinvention. Other embodiments are feasible.

The method specifically may be performed in such a way that the opticalsensor generates at least one signal indicating an intensity ofillumination for each of the pixels. The signal or a signal orinformation derived thereof may also be referred to as an intensityvalue are an intensity information. The plurality of signals, intensityvalues or the entity of intensity information may also be referred to asan image. In case a plurality of optical sensors is used, a stack ofimages or a three-dimensional image may be generated.

Thus, for each of the pixels, an analog and/or digital intensity signalmay be generated. The plurality of In case a digital intensity signal isgenerated directly or e.g. after analog-digital conversion, the digitalsignal for each pixel may be a one-bit signal or, preferably, may be asignal having an information depth of more than one bit, such as 4 bit,8 bit, 16 bit or a different number of bits.

As outlined above, the longitudinal coordinate of the object may bedetermined by using a predetermined relationship between the intensitydistribution and the longitudinal coordinate.

The intensity distribution specifically may comprise one or more of:

-   -   an intensity as a function of a transversal position of the        respective pixel in a plane perpendicular to an optical axis of        the optical sensor;    -   an intensity as a function of a pixel coordinate;    -   a distribution of a number # of pixels having a specific        intensity as a function of the intensity.

The intensity distribution specifically may approximate an intensitydistribution of an illumination by a Gaussian light beam.

The method specifically may be performed such that at least oneintensity distribution function approximating the intensity distributionis determined. The longitudinal coordinate of the object may bedetermined by using a predetermined relationship between a longitudinalcoordinate and the intensity distribution function and/or at least oneparameter derived from the intensity distribution function. Theintensity distribution function specifically may be a beam shapefunction of the light beam. The intensity distribution specifically maycomprise a mathematical function, specifically a two-dimensional or athree-dimensional mathematical function, approximating an intensityinformation contained within at least part of the pixels of the opticalsensor. The mathematical function specifically may comprise a functionof at least one pixel coordinate of the matrix of pixels. A pixelposition of the pixels of the matrix may be defined by (x, y), with x, ybeing pixel coordinates, wherein the two-dimensional orthree-dimensional mathematical function may comprise one or morefunctions selected from the group consisting of f(x), f(y), f(x, y).Therein, f(x) or f(y) are considered two-dimensional functions, whereinf(x, y) is considered a three-dimensional function. The two-dimensionalor three-dimensional mathematical function specifically may comprise oneor more mathematical functions selected from the group consisting of: abell-shaped function; a Gaussian distribution function; a Besselfunction; a Hermite-Gaussian function; a Laguerre-Gaussian function; aLorentz distribution function; a binomial distribution function; aPoisson distribution function; or at least one derivative, at least onelinear combination or at least one product comprising one or more of thelisted functions. Further, combinations of two or more mathematicalfunctions are possible. Thus, as outlined above, the two-dimensional orthree-dimensional mathematical function may comprise a combination suchas at least one product, at least one linear combination or at least onederivative of two or more mathematical functions, such as two or more ofthe above-listed mathematical functions.

In case the mathematical function comprises a product of two or morefunctions, as an example, the product may take the form f(x,y)=p(x)·q(y). Therein, p(x) and q(y) are mathematical functions, e.g.mathematical functions independently selected from the group consistingof: Gaussian functions, Hermite-Gaussian functions, Bessel functions.Other functions are possible. Further, f(x, y) generally may be arotationally symmetric function, such as f(x, y)=f(x², y²) and/or f(x,y)=f(x²+y²). This rotationally symmetric function generally may beconsidered a special case of a product of two functions. It shall benoted, however, that these examples are given for illustrative purposesonly and that many other functions are feasible.

As outlined above, the at least one intensity distribution may bedetermined. Specifically, a plurality of intensity distributions may bedetermined in a plurality of planes, wherein preferably at least oneintensity distribution for each of the planes are determined, whereinthe planes preferably are perpendicular to an optical axis of thedetector, and wherein preferably the plurality of planes are offset fromone another along the optical axis. For this purpose, specifically, thedetector may comprise a plurality of optical sensors, specifically astack of optical sensors. A change in the intensity distribution may bedetermined as a function of a longitudinal coordinate along the opticalaxis for determining the longitudinal coordinate of the object. Aplurality of intensity distribution functions may be determined, eachintensity distribution function approximating the intensity distributionin one of the planes, wherein further the longitudinal coordinate of theobject may be from the plurality of intensity distribution functions.Each of the intensity distribution functions may be a beam shapefunction of the light beam in the respective plane. At least one beamparameter may be derived from each intensity distribution function. Achange of the at least one beam parameter may be determined as afunction of a longitudinal coordinate along the optical axis fordetermining the longitudinal coordinate of the object. The at least onebeam parameter specifically may be selected from the group consistingof: a beam diameter; a beam waist; a Gaussian beam parameter. Thelongitudinal coordinate of the object specifically may be determined byusing a predetermined relationship between the beam parameters and thelongitudinal coordinate.

In the evaluation step, for each of the pixels, the signal of therespective pixel may be compared to at least one threshold in order todetermine whether the pixel is an illuminated pixel or not.

As outlined above, the threshold may be a predetermined threshold or maybe a variable threshold which may be determined according to at leastone predetermined algorithm.

In the evaluation step, at least one pixel having the highestillumination out of the pixels is determined by comparing the signals ofthe pixels. Thus, one or more of the pixels may be determined which havethe highest illumination out of the pixels of the matrix.

The knowledge about the one or more pixels having the highestillumination may be used in various ways. Thus, as an example, thisinformation may be used for determining the above-mentioned threshold.As an example, the threshold may be chosen as a fraction of the signalof the at least one pixel having the highest illumination. As outlinedabove, as an example, the threshold may be chosen by multiplying thesignal of the at least one pixel having the highest illumination with afactor of 1/e².

As outlined above, the determining of the intensity distribution maycomprise determining a number N of pixels of the optical sensor whichare illuminated by the light beam, wherein the determining of the atleast one longitudinal coordinate of the object comprises using thenumber N of pixels which are illuminated by the light beam. Thelongitudinal coordinate of the object specifically may be determined byusing a predetermined relationship between the number N of pixels whichare illuminated by the light beam and the longitudinal coordinate.

The longitudinal coordinate of the object may be determined by using apredetermined relationship between the number N of pixels which areilluminated by the light beam and the longitudinal coordinate. Asoutlined above, the predetermined relationship may be an empiricalrelationship and/or an analytical relationship. As an example, thepredetermined relationship may be based on the assumption of the lightbeam being a Gaussian light beam. Thus, as explained above with respectto the detector, the predetermined relationship may be:

${N \sim {\pi \cdot w_{0}^{2} \cdot \left( {1 + \left( \frac{z}{z_{0}} \right)^{2}} \right)}},$

-   -   wherein z is the longitudinal coordinate,    -   wherein w₀ is a minimum beam radius of the light beam when        propagating in space,    -   wherein z₀ is a Rayleigh-length of the light beam with z₀=π·w₀        ²/λ, λ being the wavelength of the light beam.

Again, preferably, the matrix of pixels may be a two-dimensional matrix.More preferably, the matrix of pixels may be a rectangular matrix.

As for the detector, the detector may comprise one optical sensor or,preferably, a plurality of the optical sensors. The optical sensors maybe stacked along an optical axis of the detector.

The detector may comprise n optical sensors. Therein, the number N_(i)of pixels which are illuminated by the light beam may be determined foreach of the optical sensors, wherein i∈{1, n} denotes the respectiveoptical sensor.

The number N_(i) of pixels which are illuminated by the light beam foreach optical sensor may be compared with at least one neighboringoptical sensor, thereby resolving an ambiguity in the longitudinalcoordinate of the object. Further, additionally or alternatively, thesensor signals of the optical sensors may be normalized for a power ofthe light beam.

In a further aspect of the present invention, a use of the detectoraccording to the present invention, such as to one or more of theembodiments disclosed above and/or according to one or more of theembodiments disclosed in further detail below, is disclosed, for apurpose of use, selected from the group consisting of: a positionmeasurement in traffic technology; an entertainment application; asecurity application; a safety application; a human-machine interfaceapplication; a tracking application; a photography application, such asan application for digital photography for arts, documentation ortechnical purposes; a use in combination with at least onetime-of-flight detector.

Thus, generally, the detector according to the present invention may beapplied in various fields of uses. Specifically, the detector may beapplied for a purpose of use, selected from the group consisting of: aposition measurement in traffic technology; an entertainmentapplication; a security application; a human-machine interfaceapplication; a tracking application; a photography application; amapping application for generating maps of at least one space, such asat least one space selected from the group of a room, a building and astreet; a mobile application; a webcam; an audio device; a dolbysurround audio system; a computer peripheral device; a gamingapplication; a camera or video application; a security application; asurveillance application; an automotive application; a transportapplication; a medical application; a sports' application; a machinevision application; a vehicle application; an airplane application; aship application; a spacecraft application; a building application; aconstruction application; a cartography application; a manufacturingapplication; a use in combination with at least one time-of-flightdetector. Additionally or alternatively, applications in local and/orglobal positioning systems may be named, especially landmark-basedpositioning and/or navigation, specifically for use in cars or othervehicles (such as trains, motorcycles, bicycles, trucks for cargotransportation), robots or for use by pedestrians. Further, indoorpositioning systems may be named as potential applications, such as forhousehold applications and/or for robots used in manufacturingtechnology.

Thus, as for the optical detectors and devices disclosed in WO2012/110924 A1 or in U.S. provisional applications 61/739,173, filed onDec. 19, 2012, 61/749,964, filed on Jan. 8, 2013, and 61/867,169, filedon Aug. 19, 2013, and international patent applicationPCT/IB2013/061095, filed on Dec. 18, 2013, the detector, the detectorsystem, the human-machine interface, the entertainment device, thetracking system or the camera according to the present invention (in thefollowing simply referred to as “the devices according to the presentinvention” may be used for a plurality of application purposes, such asone or more of the purposes disclosed in further detail in thefollowing.

Thus, firstly, the devices according to the present invention may beused in mobile phones, tablet computers, laptops, smart panels or otherstationary or mobile computer or communication applications. Thus, thedevices according to the present invention may be combined with at leastone active light source, such as a light source emitting light in thevisible range or infrared spectral range, in order to enhanceperformance. Thus, as an example, the devices according to the presentinvention may be used as cameras and/or sensors, such as in combinationwith mobile software for scanning environment, objects and livingbeings. The devices according to the present invention may even becombined with 2D cameras, such as conventional cameras, in order toincrease imaging effects. The devices according to the present inventionmay further be used for surveillance and/or for recording purposes or asinput devices to control mobile devices, especially in combination withvoice and/or gesture recognition. Thus, specifically, the devicesaccording to the present invention acting as human-machine interfaces,also referred to as input devices, may be used in mobile applications,such as for controlling other electronic devices or components via themobile device, such as the mobile phone. As an example, the mobileapplication including at least one device according to the presentinvention may be used for controlling a television set, a game console,a music player or music device or other entertainment devices.

Further, the devices according to the present invention may be used inwebcams or other peripheral devices for computing applications. Thus, asan example, the devices according to the present invention may be usedin combination with software for imaging, recording, surveillance,scanning or motion detection. As outlined in the context of thehuman-machine interface and/or the entertainment device, the devicesaccording to the present invention are particularly useful for givingcommands by facial expressions and/or body expressions. The devicesaccording to the present invention can be combined with other inputgenerating devices like e.g. mouse, keyboard, touchpad, microphone etc.Further, the devices according to the present invention may be used inapplications for gaming, such as by using a webcam. Further, the devicesaccording to the present invention may be used in virtual trainingapplications and/or video conferences

Further, the devices according to the present invention may be used inmobile audio devices, television devices and gaming devices, aspartially explained above. Specifically, the devices according to thepresent invention may be used as controls or control devices forelectronic devices, entertainment devices or the like. Further, thedevices according to the present invention may be used for eye detectionor eye tracking, such as in 2D- and 3D-display techniques, especiallywith transparent displays for augmented reality applications and/or forrecognizing whether a display is being looked at and/or from whichperspective a display is being looked at.

Further, the devices according to the present invention may be used inor as digital cameras such as DSC cameras and/or in or as reflex camerassuch as SLR cameras. For these applications, reference may be made tothe use of the devices according to the present invention in mobileapplications such as mobile phones, as disclosed above.

Further, the devices according to the present invention may be used forsecurity or surveillance applications. Thus, as an example, at least onedevice according to the present invention can be combined with one ormore digital and/or analog electronics that will give a signal if anobject is within or outside a predetermined area (e.g. for surveillanceapplications in banks or museums). Specifically, the devices accordingto the present invention may be used for optical encryption. Detectionby using at least one device according to the present invention can becombined with other detection devices to complement wavelengths, such aswith IR, x-ray, UV-VIS, radar or ultrasound detectors. The devicesaccording to the present invention may further be combined with anactive infrared light source to allow detection in low lightsurroundings. The devices according to the present invention aregenerally advantageous as compared to active detector systems,specifically since the devices according to the present invention avoidactively sending signals which may be detected by third parties, as isthe case e.g. in radar applications, ultrasound applications, LIDAR orsimilar active detector devices. Thus, generally, the devices accordingto the present invention may be used for an unrecognized andundetectable tracking of moving objects. Additionally, the devicesaccording to the present invention generally are less prone tomanipulations and irritations as compared to conventional devices.

Further, given the ease and accuracy of 3D detection by using thedevices according to the present invention, the devices according to thepresent invention generally may be used for facial, body and personrecognition and identification. Therein, the devices according to thepresent invention may be combined with other detection means foridentification or personalization purposes such as passwords, fingerprints, iris detection, voice recognition or other means. Thus,generally, the devices according to the present invention may be used insecurity devices and other personalized applications.

Further, the devices according to the present invention may be used as3D barcode readers for product identification.

In addition to the security and surveillance applications mentionedabove, the devices according to the present invention generally can beused for surveillance and monitoring of spaces and areas. Thus, thedevices according to the present invention may be used for surveying andmonitoring spaces and areas and, as an example, for triggering orexecuting alarms in case prohibited areas are violated. Thus, generally,the devices according to the present invention may be used forsurveillance purposes in building surveillance or museums, optionally incombination with other types of sensors, such as in combination withmotion or heat sensors, in combination with image intensifiers or imageenhancement devices and/or photomultipliers.

Further, the devices according to the present invention mayadvantageously be applied in camera applications such as video andcamcorder applications. Thus, the devices according to the presentinvention may be used for motion capture and 3D-movie recording.Therein, the devices according to the present invention generallyprovide a large number of advantages over conventional optical devices.Thus, the devices according to the present invention generally require alower complexity with regard to optical components. Thus, as an example,the number of lenses may be reduced as compared to conventional opticaldevices, such as by providing the devices according to the presentinvention having one lens only. Due to the reduced complexity, verycompact devices are possible, such as for mobile use. Conventionaloptical systems having two or more lenses with high quality generallyare voluminous, such as due to the general need for voluminousbeam-splitters. Further, the devices according to the present inventiongenerally may be used for focus/autofocus devices, such as autofocuscameras. Further, the devices according to the present invention mayalso be used in optical microscopy, especially in confocal microscopy.

Further, the devices according to the present invention generally areapplicable in the technical field of automotive technology and transporttechnology. Thus, as an example, the devices according to the presentinvention may be used as distance and surveillance sensors, such as foradaptive cruise control, emergency brake assist, lane departure warning,surround view, blind spot detection, rear cross traffic alert, and otherautomotive and traffic applications. Further, the devices according tothe present invention can also be used for velocity and/or accelerationmeasurements, such as by analyzing a first and second time-derivative ofposition information gained by using the detector according to thepresent invention. This feature generally may be applicable inautomotive technology, transportation technology or general traffictechnology. Applications in other fields of technology are feasible. Aspecific application in an indoor positioning system may be thedetection of positioning of passengers in transportation, morespecifically to electronically control the use of safety systems such asairbags. The use of an airbag may be prevented in case the passenger islocated as such, that the use of an airbag will cause a severe injury.

In these or other applications, generally, the devices according to thepresent invention may be used as standalone devices or in combinationwith other sensor devices, such as in combination with radar and/orultrasonic devices. Specifically, the devices according to the presentinvention may be used for autonomous driving and safety issues. Further,in these applications, the devices according to the present inventionmay be used in combination with infrared sensors, radar sensors, whichare sonic sensors, two-dimensional cameras or other types of sensors. Inthese applications, the generally passive nature of the devicesaccording to the present invention is advantageous. Thus, since thedevices according to the present invention generally do not requireemitting signals, the risk of interference of active sensor signals withother signal sources may be avoided. The devices according to thepresent invention specifically may be used in combination withrecognition software, such as standard image recognition software. Thus,signals and data as provided by the devices according to the presentinvention typically are readily processable and, therefore, generallyrequire lower calculation power than established stereovision systemssuch as LIDAR. Given the low space demand, the devices according to thepresent invention such as cameras may be placed at virtually any placein a vehicle, such as on a window screen, on a front hood, on bumpers,on lights, on mirrors or other places the like. Various detectorsaccording to the present invention such as one or more detectors basedon the effect disclosed within the present invention can be combined,such as in order to allow autonomously driving vehicles or in order toincrease the performance of active safety concepts. Thus, variousdevices according to the present invention may be combined with one ormore other devices according to the present invention and/orconventional sensors, such as in the windows like rear window, sidewindow or front window, on the bumpers or on the lights.

A combination of at least one device according to the present inventionsuch as at least one detector according to the present invention withone or more rain detection sensors is also possible. This is due to thefact that the devices according to the present invention generally areadvantageous over conventional sensor techniques such as radar,specifically during heavy rain. A combination of at least one deviceaccording to the present invention with at least one conventionalsensing technique such as radar may allow for a software to pick theright combination of signals according to the weather conditions.

Further, the devices according to the present invention generally may beused as break assist and/or parking assist and/or for speedmeasurements. Speed measurements can be integrated in the vehicle or maybe used outside the vehicle, such as in order to measure the speed ofother cars in traffic control. Further, the devices according to thepresent invention may be used for detecting free parking spaces inparking lots.

Further, the devices according to the present invention may be used inthe fields of medical systems and sports. Thus, in the field of medicaltechnology, surgery robotics, e.g. for use in endoscopes, may be named,since, as outlined above, the devices according to the present inventionmay require a low volume only and may be integrated into other devices.Specifically, the devices according to the present invention having onelens, at most, may be used for capturing 3D information in medicaldevices such as in endoscopes. Further, the devices according to thepresent invention may be combined with an appropriate monitoringsoftware, in order to enable tracking and analysis of movements. Theseapplications are specifically valuable e.g. in medical treatments andlong-distance diagnosis and tele-medicine.

Further, the devices according to the present invention may be appliedin the field of sports and exercising, such as for training, remoteinstructions or competition purposes. Specifically, the devicesaccording to the present invention may be applied in the fields ofdancing, aerobic, football, soccer, basketball, baseball, cricket,hockey, track and field, swimming, polo, handball, volleyball, rugby,sumo, judo, fencing, boxing etc. The devices according to the presentinvention can be used to detect the position of a ball, a bat, a sword,motions, etc., both in sports and in games, such as to monitor the game,support the referee or for judgment, specifically automatic judgment, ofspecific situations in sports, such as for judging whether a point or agoal actually was made.

The devices according to the present invention further may be used inrehabilitation and physiotherapy, in order to encourage training and/orin order to survey and correct movements. Therein, the devices accordingto the present invention may also be applied for distance diagnostics.

Further, the devices according to the present invention may be appliedin the field of machine vision. Thus, one or more of the devicesaccording to the present invention may be used e.g. as a passivecontrolling unit for autonomous driving and or working of robots. Incombination with moving robots, the devices according to the presentinvention may allow for autonomous movement and/or autonomous detectionof failures in parts. The devices according to the present invention mayalso be used for manufacturing and safety surveillance, such as in orderto avoid accidents including but not limited to collisions betweenrobots, production parts and living beings. In robotics, the safe anddirect interaction of humans and robots is often an issue, as robots mayseverely injure humans when they are not recognized. Devices accordingto the present invention may help robots to position objects and humansbetter and faster and allow a safe interaction. Given the passive natureof the devices according to the present invention, the devices accordingto the present invention may be advantageous over active devices and/ormay be used complementary to existing solutions like radar, ultrasound,2D cameras, IR detection etc. One particular advantage of the devicesaccording to the present invention is the low likelihood of signalinterference. Therefore multiple sensors can work at the same time inthe same environment, without the risk of signal interference. Thus, thedevices according to the present invention generally may be useful inhighly automated production environments like e.g. but not limited toautomotive, mining, steel, etc. The devices according to the presentinvention can also be used for quality control in production, e.g. incombination with other sensors like 2-D imaging, radar, ultrasound, IRetc., such as for quality control or other purposes. Further, thedevices according to the present invention may be used for assessment ofsurface quality, such as for surveying the surface evenness of a productor the adherence to specified dimensions, from the range of micrometersto the range of meters. Other quality control applications are feasible.In a manufacturing environment, the devices according to the presentinvention are especially useful for processing natural products such asfood or wood, with a complex 3-dimensional structure to avoid largeamounts of waste material. Further, devices according to the presentinvention may be used in to monitor the filling level of tanks, silosetc.

Further, the devices according to the present invention may be used inthe polls, airplanes, ships, spacecraft and other traffic applications.Thus, besides the applications mentioned above in the context of trafficapplications, passive tracking systems for aircraft, vehicles and thelike may be named. The use of at least one device according to thepresent invention, such as at least one detector according to thepresent invention, for monitoring the speed and/or the direction ofmoving objects is feasible. Specifically, the tracking of fast movingobjects on land, sea and in the air including space may be named. The atleast one device according to the present invention, such as the atleast one detector according to the present invention, specifically maybe mounted on a still-standing and/or on a moving device. An outputsignal of the at least one device according to the present invention canbe combined e.g. with a guiding mechanism for autonomous or guidedmovement of another object. Thus, applications for avoiding collisionsor for enabling collisions between the tracked and the steered objectare feasible. The devices according to the present invention generallyare useful and advantageous due to the low calculation power required,the instant response and due to the passive nature of the detectionsystem which generally is more difficult to detect and to disturb ascompared to active systems, like e.g. radar. The devices according tothe present invention are particularly useful but not limited to e.g.speed control and air traffic control devices.

The devices according to the present invention generally may be used inpassive applications. Passive applications include guidance for ships inharbors or in dangerous areas, and for aircraft at landing or starting.Wherein, fixed, known active targets may be used for precise guidance.The same can be used for vehicles driving in dangerous but well definedroutes, such as mining vehicles.

Further, as outlined above, the devices according to the presentinvention may be used in the field of gaming. Thus, the devicesaccording to the present invention can be passive for use with multipleobjects of the same or of different size, color, shape, etc., such asfor movement detection in combination with software that incorporatesthe movement into its content. In particular, applications are feasiblein implementing movements into graphical output. Further, applicationsof the devices according to the present invention for giving commandsare feasible, such as by using one or more of the devices according tothe present invention for gesture or facial recognition. The devicesaccording to the present invention may be combined with an active systemin order to work under e.g. low light conditions or in other situationsin which enhancement of the surrounding conditions is required.Additionally or alternatively, a combination of one or more the devicesaccording to the present invention with one or more IR or VIS lightsources is possible. A combination of a detector according to thepresent invention with special devices is also possible, which can bedistinguished easily by the system and its software, e.g. and notlimited to, a special color, shape, relative position to other devices,speed of movement, light, frequency used to modulate light sources onthe device, surface properties, material used, reflection properties,transparency degree, absorption characteristics, etc. The device can,amongst other possibilities, resemble a stick, a racquet, a club, a gun,a knife, a wheel, a ring, a steering wheel, a bottle, a ball, a glass, avase, a spoon, a fork, a cube, a dice, a figure, a puppet, a teddy, abeaker, a pedal, a switch, a glove, jewelry, a musical instrument or anauxiliary device for playing a musical instrument, such as a plectrum, adrumstick or the like. Other options are feasible.

Further, the devices according to the present invention generally may beused in the field of building, construction and cartography. Thus,generally, one or more devices according to the present invention may beused in order to measure and/or monitor environmental areas, e.g.countryside or buildings. Therein, one or more the devices according tothe present invention may be combined with other methods and devices orcan be used solely in order to monitor progress and accuracy of buildingprojects, changing objects, houses, etc. the devices according to thepresent invention can be used for generating three-dimensional models ofscanned environments, in order to construct maps of rooms, streets,houses, communities or landscapes, both from ground or from air.Potential fields of application may be construction, cartography, realestate management, land surveying or the like.

One or more devices according to the present invention can further beused for scanning of objects, such as in combination with CAD or similarsoftware, such as for additive manufacturing and/or 3D printing.Therein, use may be made of the high dimensional accuracy of the devicesaccording to the present invention, e.g. in x-, y- or z-direction or inany arbitrary combination of these directions, such as simultaneously.Further, the devices according to the present invention may be used ininspections and maintenance, such as pipeline inspection gauges.

As outlined above, the devices according to the present invention mayfurther be used in manufacturing, quality control or identificationapplications, such as in product identification or size identification(such as for finding an optimal place or package, for reducing wasteetc.). Further, the devices according to the present invention may beused in logisitics applications. Thus, the devices according to thepresent invention may be used for optimized loading or packingcontainers or vehicles. Further, the devices according to the presentinvention may be used for monitoring or controlling of surface damagesin the field of manufacturing, for monitoring or controlling rentalobjects such as rental vehicles, and/or for insurance applications, suchas for assessment of damages. Further, the devices according to thepresent invention may be used for identifying a size of material, objector tools, such as for optimal material handling, especially incombination with robots. Further, the devices according to the presentinvention may be used for process control in production, e.g. forobserving filling level of tanks. Further, the devices according to thepresent invention may be used for maintenance of production assets like,but not limited to, tanks, pipes, reactors, tools etc. Further, thedevices according to the present invention may be used for analyzing3D-quality marks. Further, the devices according to the presentinvention may be used in manufacturing tailor-made goods such as toothinlays, dental braces, prosthesis, clothes or the like. The devicesaccording to the present invention may also be combined with one or more3D-printers for rapid prototyping, 3D-copying or the like. Further, thedevices according to the present invention may be used for detecting theshape of one or more articles, such as for anti-product piracy and foranti-counterfeiting purposes.

Thus, specifically, the present application may be applied in the fieldof photography. Thus, the detector may be part of a photographic device,specifically of a digital camera. Specifically, the detector may be usedfor 3D photography, specifically for digital 3D photography. Thus, thedetector may form a digital 3D camera or may be part of a digital 3Dcamera. As used herein, the term photography generally refers to thetechnology of acquiring image information of at least one object. Asfurther used herein, a camera generally is a device adapted forperforming photography. As further used herein, the term digitalphotography generally refers to the technology of acquiring imageinformation of at least one object by using a plurality oflight-sensitive elements adapted to generate electrical signalsindicating an intensity and/or color of illumination, preferably digitalelectrical signals. As further used herein, the term 3D photographygenerally refers to the technology of acquiring image information of atleast one object in three spatial dimensions. Accordingly, a 3D camerais a device adapted for performing 3D photography. The camera generallymay be adapted for acquiring a single image, such as a single 3D image,or may be adapted for acquiring a plurality of images, such as asequence of images. Thus, the camera may also be a video camera adaptedfor video applications, such as for acquiring digital video sequences.

Thus, generally, the present invention further refers to a camera,specifically a digital camera, more specifically a 3D camera or digital3D camera, for imaging at least one object. As outlined above, the termimaging, as used herein, generally refers to acquiring image informationof at least one object. The camera comprises at least one detectoraccording to the present invention. The camera, as outlined above, maybe adapted for acquiring a single image or for acquiring a plurality ofimages, such as image sequence, preferably for acquiring digital videosequences. Thus, as an example, the camera may be or may comprise avideo camera. In the latter case, the camera preferably comprises a datamemory for storing the image sequence.

The detector or the camera including the detector, having the at leastone optical sensor, specifically the above-mentioned FiP sensor, mayfurther be combined with one or more additional sensors. Thus, at leastone camera having the at least one optical sensor, specifically the atleast one above-mentioned FiP sensor, may be combined with at least onefurther camera, which may be a conventional camera and/or e.g. a stereocamera. Further, one, two or more cameras having the at least oneoptical sensor, specifically the at least one above-mentioned FiPsensor, may be combined with one, two or more digital cameras. As anexample, one or two or more two-dimensional digital cameras may be usedfor calculating the depth from stereo information and from the depthinformation gained by the detector according to the present invention.

Specifically in the field of automotive technology, in case a camerafails, the detector according to the present invention may still bepresent for measuring a longitudinal coordinate of an object, such asfor measuring a distance of an object in the field of view. Thus, byusing the detector according to the present invention in the field ofautomotive technology, a failsafe function may be implemented.Specifically for automotive applications, the detector according to thepresent invention provides the advantage of data reduction. Thus, ascompared to camera data of conventional digital cameras, data obtainedby using the detector according to the present invention, i.e. adetector having the at least one optical sensor, specifically the atleast one FiP sensor, may provide data having a significantly lowervolume. Specifically in the field of automotive technology, a reducedamount of data is favorable, since automotive data networks generallyprovide lower capabilities in terms of data transmission rate.

The detector according to the present invention may further comprise oneor more light sources. Thus, the detector may comprise one or more lightsources for illuminating the at least one object, such that e.g.illuminated light is reflected by the object. The light source may be acontinuous light source or maybe discontinuously emitting light sourcesuch as a pulsed light source. The light source may be a uniform lightsource or may be a nonuniform light source or a patterned light source.Thus, as an example, in order for the detector to measure the at leastone longitudinal coordinate, such as to measure the depth of at leastone object, a contrast in the illumination or in the scene captured bythe detector is advantageous. In case no contrast is present by naturalillumination, the detector may be adapted, via the at least one optionallight source, to fully or partially illuminate the scene and/or at leastone object within the scene, preferably with patterned light. Thus, asan example, the light source may project a pattern into a scene, onto awall or onto at least one object, in order to create an increasedcontrast within an image captured by the detector.

The at least one optional light source may generally emit light in oneor more of the visible spectral range, the infrared spectral range orthe ultraviolet spectral range. Preferably, the at least one lightsource emits light at least in the infrared spectral range.

The detector may also be adapted to automatically illuminate the scene.Thus, the detector, such as the evaluation device, may be adapted toautomatically control the illumination of the scene captured by thedetector or a part thereof. Thus, as an example, the detector may beadapted to recognize in case large areas provide low contrast, therebymaking it difficult to measure the longitudinal coordinates, such asdepth, within these areas. In these cases, as an example, the detectormay be adapted to automatically illuminate these areas with patternedlight, such as by projecting one or more patterns into these areas.

As used within the present invention, the expression “position”generally refers to at least one item of information regarding one ormore of an absolute position and an orientation of one or more points ofthe object. Thus, specifically, the position may be determined in acoordinate system of the detector, such as in a Cartesian coordinatesystem. Additionally or alternatively, however, other types ofcoordinate systems may be used, such as polar coordinate systems and/orspherical coordinate systems.

As outlined above and as will be outlined in further detail below, thepresent invention preferably may be applied in the field ofhuman-machine interfaces, in the field of sports and/or in the field ofcomputer games. Thus, preferably, the object may be selected from thegroup consisting of: an article of sports equipment, preferably anarticle selected from the group consisting of a racket, a club, a bat;an article of clothing; a hat; a shoe. Other embodiments are feasible.

As used herein, the object generally may be an arbitrary object, chosenfrom a living object and a non-living object. Thus, as an example, theat least one object may comprise one or more articles and/or one or moreparts of an article. Additionally or alternatively, the object may be ormay comprise one or more living beings and/or one or more parts thereof,such as one or more body parts of a human being, e.g. a user, and/or ananimal.

With regard to the coordinate system for determining the position of theobject, which may be a coordinate system of the detector, the detectormay constitute a coordinate system in which an optical axis of thedetector forms the z-axis and in which, additionally, an x-axis and ay-axis may be provided which are perpendicular to the z-axis and whichare perpendicular to each other. As an example, the detector and/or apart of the detector may rest at a specific point in this coordinatesystem, such as at the origin of this coordinate system. In thiscoordinate system, a direction parallel or antiparallel to the z-axismay be regarded as a longitudinal direction, and a coordinate along thez-axis may be considered a longitudinal coordinate. An arbitrarydirection perpendicular to the longitudinal direction may be considereda transversal direction, and an x- and/or y-coordinate may be considereda transversal coordinate.

Alternatively, other types of coordinate systems may be used. Thus, asan example, a polar coordinate system may be used in which the opticalaxis forms a z-axis and in which a distance from the z-axis and a polarangle may be used as additional coordinates. Again, a direction parallelor antiparallel to the z-axis may be considered a longitudinaldirection, and a coordinate along the z-axis may be considered alongitudinal coordinate. Any direction perpendicular to the z-axis maybe considered a transversal direction, and the polar coordinate and/orthe polar angle may be considered a transversal coordinate.

As used herein, a detector for determining a position of at least oneobject generally is a device adapted for providing at least one item ofinformation on the position of the at least one object and/or a partthereof. Thus, the position may refer to an item of information fullydescribing the position of the object or a part thereof, preferably inthe coordinate system of the detector, or may refer to a partialinformation, which only partially describes the position. The detectorgenerally may be a device adapted for detecting light beams, such as thelight beams traveling from the beacon devices towards the detector.

The evaluation device and the detector may fully or partially beintegrated into a single device. Thus, generally, the evaluation devicealso may form part of the detector. Alternatively, the evaluation deviceand the detector may fully or partially be embodied as separate devices.The detector may comprise further components.

The detector may be a stationary device or a mobile device. Further, thedetector may be a stand-alone device or may form part of another device,such as a computer, a vehicle or any other device. Further, the detectormay be a hand-held device. Other embodiments of the detector arefeasible.

As used herein, an optical sensor generally is a device which isdesigned to generate at least one longitudinal sensor signal in a mannerdependent on an illumination of the optical sensor by the light beam.Preferably, as outlined above and as will be outlined in further detailbelow, the detector according to the present invention may comprise aplurality of optical sensors, preferably as a sensor stack.

The at least one optical sensor may comprise one or more photodetectors, preferably one or more organic photodetectors and, mostpreferably, one or more dye-sensitized organic solar cells (DSCs, alsoreferred to as dye solar cells), such as one or more soliddye-sensitized organic solar cells (sDSCs). Thus, preferably, thedetector may comprise one or more DSCs (such as one or more sDSCs)acting as the at least one optical sensor, preferably a stack of aplurality of DSCs (preferably a stack of a plurality of sDSCs) acting asthe at least one optical sensor. Additionally or alternatively, thedetector may comprise other types of optical sensors, as outlined infurther detail above.

As outlined above, the detector according to the present inventionspecifically may comprise a plurality of the optical sensors, which arealso referred to as pixelated sensors or pixelated optical sensors.Specifically, the detector may comprise a stack of the optical sensors,such as a stack of transparent optical sensors.

Thus, the detector may comprise at least one stack of the opticalsensors, and the detector may be adapted to acquire a three-dimensionalimage of a scene within a field of view of the detector. The opticalsensors of the stack may have identical spectral properties, such asidentical or uniform absorption spectra. Alternatively, the opticalsensors of the stack may have differing spectral properties. Thus, thestack may comprise at least one first optical sensor having a firstspectral sensitivity and at least one second optical sensor having asecond spectral sensitivity, wherein the first spectral sensitivity andthe second spectral sensitivity are different. The stack specificallymay comprise optical sensors having differing spectral properties in analternating sequence. The detector may be adapted to acquire amulticolor three-dimensional image, preferably a full-colorthree-dimensional image, by evaluating sensor signals of the opticalsensors having differing spectral properties.

Thus, generally, the pixelated sensors, specifically the transparentpixelated sensors, may be used to record images at different distancesto the detector, such as at different distances to the at least oneoptional transfer device and, more specifically, to at least one lens ofthe detector. If more than one pixelated sensor is used, several imagesat different distances to the detector may be recorded simultaneously.Preferably the distances to the lens are as such, that different partsof the images are in focus. Thus, the images can be used inimage-processing techniques known as focus stacking, z-stacking, focalplane merging. One application of these techniques is obtaining imageswith greater depth of field, which is especially helpful in imagingtechniques with typically very shallow depth of field such as macrophotography or optical microscopy. Another application is to obtaindistance information using algorithms, convolution based algorithms suchas depth from focus or depth from defocus. Another application is tooptimize the images to obtain a greater artistic or scientific merit.

The detector having the plurality of pixelated sensors also may be usedto record a light-field behind a lens or lens system of the detector,comparable to a plenoptic or light-field camera. Thus, specifically, thedetector may be embodied as a light-field camera adapted for acquiringimages in multiple focal planes, such as simultaneously. The termlight-field, as used herein, generally refers to the spatial lightpropagation of light inside the detector such as inside camera. Thedetector according to the present invention, specifically having a stackof optical sensors, may have the capability of directly recording alight-field within the detector or camera, such as behind a lens. Theplurality of pixelated sensors may record images at different distancesfrom the lens. Using, e.g., convolution-based algorithms such as “depthfrom focus” or “depth from defocus”, the propagation direction, focuspoints, and spread of the light behind the lens can be modeled. From themodeled propagation of light behind the lens, images at variousdistances to the lens can be extracted, the depth of field can beoptimized, pictures that are in focus at various distances can beextracted, or distances of objects can be calculated. Furtherinformation may be extracted.

Once the light propagation inside the detector, such as behind a lens ofthe detector, is modeled and/or recorded, this knowledge of lightpropagation provides a large number of advantages. Thus, the light-fieldmay be recorded in terms of beam parameters for one or more light beamsof a scene captured by the detector. As an example, for each light beamrecorded, two or more beam parameters may be recorded, such as one ormore Gaussian beam parameters, e.g. a beam waist, a minimum beam waistas a focal point, a Rayleigh length, or other beam parameters. Severalrepresentations of light beams may be used and beam parameters may bechosen accordingly.

This knowledge of light propagation, as an example, allows for slightlymodifying the observer position after recording an image stack usingimage processing techniques. In a single image, an object may be hiddenbehind another object and is not visible. However, if the lightscattered by the hidden object reaches the lens and through the lens oneor more of the sensors, the object may be made visible, by changing thedistance to the lens and/or the image plane relative to the opticalaxis, or even using non-planar image planes. The change of the observerposition may be compared to looking at a hologram, in which changing theobserver position slightly changes the image.

The knowledge of light propagation inside the detector, such as bymodeling the light propagation behind the lens, may further allow forstoring the image information in a more compact way as compared toconventional technology of storing each image recorded by eachindividual optical sensor. The memory demand for storing all images ofeach optical sensor typically scales with the number of sensors timesthe number of pixels. The memory demand of the light propagation scaleswith the number of modeled light beams times the number of parametersper light beam. Typical model functions for light beams may beGaussians, Lorentzians, Bessel functions, especially spherical Besselfunctions, other functions typically used for describing diffractioneffects in physics, or typical spread functions used in depth fromdefocus techniques such as point spread functions, line spread functionsor edge spread functions.

The use of several pixelated sensors further allows for correcting lenserrors in an image processing step after recording the images. Opticalinstruments often become expensive and challenging in construction, whenlens errors need to be corrected. These are especially problematic inmicroscopes and telescopes. In microscopes, a typical lens error is thatrays of varying distance to the optical axis are distorted differently(spherical aberration). In telescopes, varying the focus may occur fromdiffering temperatures in the atmosphere. Static errors such asspherical aberration or further errors from production may be correctedby determining the errors in a calibration step and then using a fixedimage processing such as fixed set of pixels and sensor, or moreinvolved processing techniques using light propagation information. Incases in which lens errors are strongly time-dependent, i.e. dependenton weather conditions in telescopes, the lens errors may be corrected byusing the light propagation behind the lens, calculating extended depthof field images, using depth from focus techniques, and others.

As outlined above, the detector according to the present invention mayfurther allow for color detection. For color detection in stacks ofseveral pixelated sensors, the single stacks may have pixels that havedifferent absorption properties, equal or similar to the so-called Bayerpattern, and color information may be obtained by interpolationtechniques. A further method is to use sensors of alternating color,wherein different sensors in the stack may record different colors. In aBayer pattern, color may be interpolated between same-color pixels. In astack of sensors, the image information such as color and brightness,etc., can also be obtained by interpolation techniques.

The evaluation device may be or may comprise one or more integratedcircuits, such as one or more application-specific integrated circuits(ASICs), and/or one or more data processing devices, such as one or morecomputers, preferably one or more microcomputers and/ormicrocontrollers. Additional components may be comprised, such as one ormore preprocessing devices and/or data acquisition devices, such as oneor more devices for receiving and/or preprocessing of the sensorsignals, such as one or more AD-converters and/or one or more filters.Further, the evaluation device may comprise one or more measurementdevices, such as one or more measurement devices for measuringelectrical currents and/or electrical voltages. Thus, as an example, theevaluation device may comprise one or more measurement devices formeasuring electrical currents through and/or electrical voltages of thepixels. Further, the evaluation device may comprise one or more datastorage devices. Further, the evaluation device may comprise one or moreinterfaces, such as one or more wireless interfaces and/or one or morewire-bound interfaces.

The at least one evaluation device may be adapted to perform at leastone computer program, such as at least one computer program adapted forperforming or supporting one or more or even all of the method steps ofthe method according to the present invention. As an example, one ormore algorithms may be implemented which, by using the sensor signals asinput variables, may determine the position of the object.

The evaluation device can be connected to or may comprise at least onefurther data processing device that may be used for one or more ofdisplaying, visualizing, analyzing, distributing, communicating orfurther processing of information, such as information obtained by theoptical sensor and/or by the evaluation device. The data processingdevice, as an example, may be connected or incorporate at least one of adisplay, a projector, a monitor, an LCD, a TFT, a loudspeaker, amultichannel sound system, an LED pattern, or a further visualizationdevice. It may further be connected or incorporate at least one of acommunication device or communication interface, a connector or a port,capable of sending encrypted or unencrypted information using one ormore of email, text messages, telephone, bluetooth, Wi-Fi, infrared orinternet interfaces, ports or connections. It may further be connectedor incorporate at least one of a processor, a graphics processor, a CPU,an Open Multimedia Applications Platform (OMAP™), an integrated circuit,a system on a chip such as products from the Apple A series or theSamsung S3C2 series, a microcontroller or microprocessor, one or morememory blocks such as ROM, RAM, EEPROM, or flash memory, timing sourcessuch as oscillators or phase-locked loops, counter-timers, real-timetimers, or power-on reset generators, voltage regulators, powermanagement circuits, or DMA controllers. Individual units may further beconnected by buses such as AMBA buses.

The evaluation device and/or the data processing device may be connectedby or have further external interfaces or ports such as one or more ofserial or parallel interfaces or ports, USB, Centronics Port, FireWire,HDMI, Ethernet, Bluetooth, RFID, Wi-Fi, USART, or SPI, or analoginterfaces or ports such as one or more of ADCs or DACs, or standardizedinterfaces or ports to further devices such as a 2D-camera device usingan RGB-interface such as CameraLink. The evaluation device and/or thedata processing device may further be connected by one or more ofinterprocessor interfaces or ports, FPGA-FPGA-interfaces, or serial orparallel interfaces ports. The evaluation device and the data processingdevice may further be connected to one or more of an optical disc drive,a CD-RW drive, a DVD+RW drive, a flash drive, a memory card, a diskdrive, a hard disk drive, a solid state disk or a solid state hard disk.

The evaluation device and/or the data processing device may be connectedby or have one or more further external connectors such as one or moreof phone connectors, RCA connectors, VGA connectors, hermaphroditeconnectors, USB connectors, HDMI connectors, 8P8C connectors, BCNconnectors, IEC 60320 C14 connectors, optical fiber connectors,D-subminiature connectors, RF connectors, coaxial connectors, SCARTconnectors, XLR connectors, and/or may incorporate at least one suitablesocket for one or more of these connectors.

Possible embodiments of a single device incorporating one or more of thedetectors according to the present invention, the evaluation device orthe data processing device, such as incorporating one or more of theoptical sensor, optical systems, evaluation device, communicationdevice, data processing device, interfaces, system on a chip, displaydevices, or further electronic devices, are: mobile phones, personalcomputers, tablet PCs, televisions, game consoles or furtherentertainment devices. In a further embodiment, the 3D-camerafunctionality which will be outlined in further detail below may beintegrated in devices that are available with conventional 2D-digitalcameras, without a noticeable difference in the housing or appearance ofthe device, where the noticeable difference for the user may only be thefunctionality of obtaining and or processing 3D information.

Specifically, an embodiment incorporating the detector and/or a partthereof such as the evaluation device and/or the data processing devicemay be: a mobile phone incorporating a display device, a data processingdevice, the optical sensor, optionally the sensor optics, and theevaluation device, for the functionality of a 3D camera. The detectoraccording to the present invention specifically may be suitable forintegration in entertainment devices and/or communication devices suchas a mobile phone.

A further embodiment of the present invention may be an incorporation ofthe detector or a part thereof such as the evaluation device and/or thedata processing device in a device for use in automotive, for use inautonomous driving or for use in car safety systems such as Daimler'sIntelligent Drive system, wherein, as an example, a device incorporatingone or more of the optical sensors, optionally one or more opticalsystems, the evaluation device, optionally a communication device,optionally a data processing device, optionally one or more interfaces,optionally a system on a chip, optionally one or more display devices,or optionally further electronic devices may be part of a vehicle, acar, a truck, a train, a bicycle, an airplane, a ship, a motorcycle. Inautomotive applications, the integration of the device into theautomotive design may necessitate the integration of the optical sensor,optionally optics, or device at minimal visibility from the exterior orinterior. The detector or a part thereof such as the evaluation deviceand/or the data processing device may be especially suitable for suchintegration into automotive design.

As used herein, the term light generally refers to electromagneticradiation in one or more of the visible spectral range, the ultravioletspectral range and the infrared spectral range. Therein, the termvisible spectral range generally refers to a spectral range of 380 nm to780 nm. The term infrared spectral range generally refers toelectromagnetic radiation in the range of 780 nm to 1 mm, preferably inthe range of 780 nm to 3.0 micrometers. The term ultraviolet spectralrange generally refers to electromagnetic radiation in the range of 1 nmto 380 nm, preferably in the range of 100 nm to 380 nm. Preferably,light as used within the present invention is visible light, i.e. lightin the visible spectral range.

The term light beam generally refers to an amount of light emittedand/or reflected into a specific direction. Thus, the light beam may bea bundle of the light rays having a predetermined extension in adirection perpendicular to a direction of propagation of the light beam.Preferably, the light beams may be or may comprise one or more Gaussianlight beams which may be characterized by one or more Gaussian beamparameters, such as one or more of a beam waist, a Rayleigh-length orany other beam parameter or combination of beam parameters suited tocharacterize a development of a beam diameter and/or a beam propagationin space.

As outlined above, preferably, specifically in case a plurality ofoptical sensors is provided, at least one of the optical sensors is atransparent optical sensor. Thus, in case a stack of the optical sensorsis provided, preferably all optical sensors of the plurality and/or thestack or all optical sensors of the plurality and/or the stack but oneoptical sensor are transparent. As an example, in case a stack ofoptical sensors is provided, wherein the optical sensors are arrangedalong the optical axis of the detector, preferably all optical sensorsbut the last optical sensor furthest away from the object may betransparent optical sensors. The last optical sensor, i.e. the opticalsensor on the side of the stack facing away from the object, may be atransparent optical sensor or an intransparent optical sensor. Exemplaryembodiments will be given below.

As outlined above, the optical sensor preferably comprises an organicphotodetector such as an organic solar cell and/or an sDSC. In order toprovide a transparent optical sensor, the optical sensor may have twotransparent electrodes. Thus, at least one first electrode and/or the atleast one second electrode of the optical sensor preferably may fully orpartially be transparent. In order to provide a transparent electrode, atransparent conductive oxide may be used (TCO), such as indium-doped tinoxide (ITO) and/or fluorine-doped tin oxide (FTO). Additionally oralternatively, metal layers may be used, such as thin layers of one ormore metal selected from the group consisting of Al, Ag, Au and Pt, suchas metal layers having a thickness of below 50 nm, preferably below 40nm. In order to support connectivity, additionally or alternatively,conductive organic materials may be used, such as conductive polymers.Thus, as an example, one or more of the electrodes of the at least oneoptical sensor may comprise one or more transparent conductive polymers.As an example, one or more conductive polymer films having a surfaceconductivity of at least 0.00001 S/cm, at least 0.001 S/cm or at least0.01 S/cm may be used, preferably of at least 0.1 S/cm or, morepreferably, of at least 1 S/cm or even at least 10 S/cm or at least 100S/cm. As an example, the at least one conductive polymer may be selectedfrom the group consisting of: a poly-3,4-ethylenedioxythiophene (PEDOT),preferably PEDOT being electrically doped with at least one counter ion,more preferably PEDOT doped with sodium polystyrene sulfonate(PEDOT:PSS); a polyaniline (PANI); a polythiophene. Preferably, theconductive polymer provides an electric resistivity of 0.1-20 kΩ betweenthe partial electrodes, preferably an electric resistivity of 0.5-5.0 kΩand, more preferably, an electric resistivity of 1.0-3.0 kΩ. Generally,as used herein, a conductive material may be a material which has aspecific electrical resistance of less than 10⁴, less than 10³, lessthan 10², or of less than 10 Ωm. Preferably, the conductive material hasa specific electrical resistance of less than 10⁻¹, less than 10⁻², lessthan 10⁻³, less than 10⁻⁵, or less than 10⁻⁶ Ωm. Most preferably, thespecific electrical resistance of the conductive material is less than5×10⁻⁷ Ωm or is less than 1×10⁻⁷ Ωm, particularly in the range of thespecific electrical resistance of aluminum.

Generally, the optical sensor may comprise an arbitrary optical sensorhaving a plurality of pixels arranged in a matrix. The optical sensor,as outlined above and for reasons of example only, may comprise at leastone semiconductor detector, in particular an organic semiconductordetector comprising at least one organic material, preferably an organicsolar cell and particularly preferably a dye solar cell ordye-sensitized solar cell, in particular a solid dye solar cell or asolid dye-sensitized solar cell. Preferably, the optical sensor is orcomprises a DSC or sDSC. Thus, preferably, the optical sensor comprisesat least one first electrode, at least one n-semiconducting metal oxide,at least one dye, at least one p-semiconducting organic material,preferably a solid p-semiconducting organic material, and at least onesecond electrode. In a preferred embodiment, the optical sensorcomprises at least one DSC or, more preferably, at least one sDSC. Asoutlined above, preferably, the at least one optical sensor is atransparent optical sensor or comprises at least one transparent opticalsensor. Thus, preferably, both the first electrode and the secondelectrode are transparent or, in case a plurality of optical sensors isprovided, at least one of the optical sensors is designed such that boththe first electrode and the second electrode are transparent. Asoutlined above, in case a stack of optical sensors is provided,preferably all optical sensors of the stack are transparent but the lastoptical sensor of the stack furthest away from the object. The lastoptical sensor may be transparent or intransparent. In the latter case,the last optical sensor may be designed such that its electrode facingtowards the object is transparent, whereas its electrode facing awayfrom the object may be intransparent.

As outlined above, the detector preferably has a plurality of opticalsensors. More preferably, the plurality of optical sensors is stacked,such as along the optical axis of the detector. Thus, the opticalsensors may form an optical sensor stack. The optical sensor stackpreferably may be oriented such that the sensor regions of the opticalsensors are oriented perpendicular to the optical axis. Thus, as anexample, sensor areas or sensor surfaces of the single optical sensorsmay be oriented in parallel, wherein slight angular tolerances might betolerable, such as angular tolerances of no more than 10°, preferably ofno more than 5°.

In case stacked optical sensors are provided, the at least onetransversal optical sensor preferably fully or partially may be locatedon a side of the stacked optical sensors facing towards the object. Theat least one optional transversal optical sensor may as well be part ofthe sensor stack. Generally, any other arrangement is feasible. Theoptical sensors preferably are arranged such that the at least one lightbeam traveling from the object towards the detector illuminates alloptical sensors, preferably sequentially. For the purpose of normalizingthe sensor signals of the optical sensors, use may be made of the factthat, in case the single longitudinal sensor signals are generated byone and the same light beam, differences in the single longitudinalsensor signals are generally only due to differences in thecross-sections of the light beam at the location of the respectivesensor regions of the single optical sensors. Thus, by comparing thesingle longitudinal sensor signals, information on a beam cross-sectionmay be generated even if the overall power of the light beam is unknown.

Further, the above-mentioned stacking of the optical sensors and thegeneration of a plurality of longitudinal sensor signals by thesestacked optical sensors may be used by the evaluation device in order toresolve an ambiguity in a known relationship between a beamcross-section of the light beam and the longitudinal coordinate of thebeacon device. Thus, even if the beam properties of the light beampropagating from the beacon device to the detector are known fully orpartially, it is known that, in many beams, the beam cross-sectionnarrows before reaching a focal point and, afterwards, widens again.Such is the case e.g. for Gaussian light beams. Thus, before and after afocal point in which the light beam has the narrowest beamcross-section, positions along the axis of propagation of the light beamoccur in which the light beam has the same cross-section. Thus, as anexample, at a distance z0 before and after the focal point, thecross-section of the light beam is identical. Thus, in case only oneoptical sensor is used, a specific cross-section of the light beam mightbe determined, in case the overall power or intensity of the light beamis known. By using this information, the distance z0 of the respectiveoptical sensor from the focal point might be determined. However, inorder to determine whether the respective optical sensor is locatedbefore or behind the focal point, additional information may berequired, such as a history of movement of the object and/or thedetector and/or information on whether the detector is located before orbehind the focal point. In typical situations, this additionalinformation may not be available. Therefore, by using a plurality ofoptical sensors, additional information may be gained in order toresolve the above-mentioned ambiguity. Thus, in case the evaluationdevice, by evaluating the longitudinal sensor signals, recognizes thatthe beam cross-section of the light beam on a first optical sensor islarger than the beam cross-section of the light beam on a second opticalsensor, wherein the second optical sensor is located behind the firstoptical sensor, the evaluation device may determine that the light beamis still narrowing and that the location of the first optical sensor issituated before the focal point of the light beam. Contrarily, in casethe beam cross-section of the light beam on the first optical sensor issmaller than the beam cross-section of the light beam on the secondoptical sensor, the evaluation device may determine that the light beamis widening and that the location of the second optical sensor issituated behind the focal point. Thus, generally, the evaluation devicemay be adapted to recognize whether the light beam widens or narrows, bycomparing the longitudinal sensor signals of different longitudinalsensors.

The optical sensor stack preferably may comprise at least three opticalsensors, more preferably at least four optical sensors, even morepreferably at least five optical sensors or even at least six opticalsensors. By tracking the longitudinal sensor signals of the opticalsensors, even a beam profile of the light beam might be evaluated.

As used herein and as used in the following, the diameter of the lightbeam or, equivalently, a beam waist or twice the beam waist of the lightbeam might be used to characterize the beam cross-section of the lightbeam at a specific location. As outlined above, a known relationshipmight be used between the longitudinal position of the object and/or therespective beacon device, i.e. the beacon device emitting and/orreflecting the light beam, and the beam cross-section in order todetermine the longitudinal coordinate of the beacon device by evaluatingthe at least one longitudinal sensor signal. As an example, as outlinedabove, a Gaussian relationship might be used, assuming that the lightbeam propagates at least approximately in a Gaussian manner. For thispurpose, the light beam might be shaped appropriately, such as by usingan illumination source generating a light beam having known propagationproperties, such as a known Gaussian profile. For this purpose, theillumination source itself may generate the light beam having the knownproperties, which, for example, is the case for many types of lasers, asthe skilled person knows. Additionally or alternatively, theillumination source and/or the detector may have one or more transferdevices, such as one or more beam-shaping elements, such as one or morelenses and/or one or more diaphragms, in order to provide a light beamhaving known properties, as the skilled person will recognize. Thus, asan example, one or more transfer devices may be provided, such as one ormore transfer devices having known beam-shaping properties. Additionallyor alternatively, the illumination source and/or the detector, such asthe at least one optional transfer device, may have one or morewavelength-selective elements, such as one or more filters, such as oneor more filter elements for filtering out wavelengths outside anexcitation maximum of the at least one transversal optical sensor and/orthe at least one optical sensor.

Thus, generally, the evaluation device may be adapted to compare thebeam cross-section and/or the diameter of the light beam with known beamproperties of the light beam in order to determine the at least one itemof information on the longitudinal position of the object, preferablyfrom a known dependency of a beam diameter of the light beam on at leastone propagation coordinate in a direction of propagation of the lightbeam and/or from a known Gaussian profile of the light beam.

As outlined above, the at least one optical sensor or pixelated sensorof the detector, as an example, may be or may comprise at least oneorganic optical sensor. As an example, the at least one optical sensormay be or may comprise at least one organic solar cell, such as at leastone dye-sensitized solar cell (DSC), preferably at least one solid DSCor sDSC. Specifically, the at least one optical sensor may be or maycomprise at least one optical sensor capable of showing an effect of thesensor signal being dependent on a photon density or flux of photons. InFIP sensors, given the same total power p of illumination, the sensorsignal i is generally dependent on a flux F of photons, i.e. the numberof photons per unit area. In other words, the at least one opticalsensor may comprise at least one optical sensor which is defined as aFIP sensor, i.e. as an optical sensor capable of providing a sensorsignal, the sensor having at least one sensor region, such as aplurality of sensor regions like e.g. pixels, wherein the sensor signal,given the same total power of illumination of the sensor region by thelight beam, is dependent on a geometry of the illumination, inparticular on a beam cross section of the illumination on the sensorarea. This effect including potential embodiments of optical sensorsexhibiting this effect (such as sDSCs) is disclosed in further detail inWO 2012/110924 A1, in U.S. provisional applications 61/739,173, filed onDec. 19, 2012, 61/749,964, filed on Jan. 8, 2013, and 61/867,169, filedon Aug. 19, 2013, and international patent applicationPCT/IB2013/061095, filed on Dec. 18, 2013. The embodiments of opticalsensors exhibiting the FiP effect as disclosed in these prior artdocuments, which all are included herewith by reference, may also beused as optical sensors in the detector according to the presentinvention, besides the fact that the optical sensors or at least one ofthe optical sensors are pixelated. Thus, the optical sensors as used inone or more of the above-mentioned prior art documents, in a pixelatedfashion, may also be used in the context of the present invention. Apixelation may simply be achieved by an appropriate patterning of thefirst and/or second electrodes of these optical sensors. Thus, each ofthe pixels of the pixelated optical sensors exhibiting theabove-mentioned FiP-effect may, by itself, form a FiP sensor.

Thus, the detector according to the present invention specifically mayfully or partially be embodied as a pixelated FiP camera, i.e. as acamera in which the at least one optical sensor or, in case a pluralityof optical sensors is provided, at least one of the optical sensors, areembodied as pixelated FiP sensors. In pixeled FiP-cameras, pictures maybe recorded in a similar way as disclosed above in the setup of thelight-field camera. Thus, the detector may comprise a stack of opticalsensors, each optical sensor being embodied as a pixelated FiP sensor.Pictures may be recorded at different distances from the lens. A depthcan be calculated from these pictures using approaches such asdepth-from-focus and/or depth-from-defocus.

The FiP measurement typically necessitates two or more FiP sensors suchas organic solar cells exhibiting the FiP effect. The photon density onthe different cells may vary as such, that a current ratio of at least1/100 is obtained between a cell close to focus and a cell out of focus.If the ratio is closer to 1, the measurement may be imprecise.

The at least one evaluation device may specifically be embodied tocompare signals generated by pixels of different optical sensors, thepixels being located on a line parallel to an optical axis of thedetector. A light cone of the light beam might cover a single pixel inthe focus region. In the out-of-focus region, only a small part of thelight cone will cover the pixel. Thus, in a stack of pixelated FiPsensors, the signal of the pixel of the sensor being out of focus willgenerally be much smaller than the signal of the pixel of the sensorbeing in focus. Consequently, the signal ratio will improve. For acalculation of the distance between the object and the detector, morethan two optical sensors may be used in order to further increase theprecision.

Thus, generally, the at least one optical sensor may comprise at leastone stack of optical sensors, each optical sensor having at least onesensor region and being capable of providing at least one sensor signal,wherein the sensor signal, given the same total power of illumination ofthe sensor region by the light beam, is dependent on a geometry of theillumination, in particular on a beam cross section of the illuminationon the sensor area, wherein the evaluation device may be adapted tocompare at least one sensor signal generated by at least one pixel of afirst one of the optical sensors with at least one sensor signalgenerated by at least one pixel of a second one of the optical sensors,specifically for determining a distance between the object and thedetector and/or a z-coordinate of the object. The evaluation device mayfurther be adapted for evaluating the sensor signals of the pixels.Thus, one or more evaluation algorithms may be used. Additionally oralternatively, other means of evaluation may be used, such as by usingone or more lookup tables, such as one or more lookup tables comprisingFiP sensor signal values or ratios thereof and correspondingz-coordinates of the object and/or corresponding distances between theobject and the detector. An analysis of several FiP-signals, taking intoaccount the distance to the lens and/or a distance between the opticalsensors may also result in information regarding the light beam, such asthe spread of the light beam and, thus, the conventional FiP-distance.

As outlined above, the present invention further relates to ahuman-machine interface for exchanging at least one item of informationbetween a user and a machine. The human-machine interface as proposedmay make use of the fact that the above-mentioned detector in one ormore of the embodiments mentioned above or as mentioned in furtherdetail below may be used by one or more users for providing informationand/or commands to a machine. Thus, preferably, the human-machineinterface may be used for inputting control commands.

Generally, as used herein, the at least one position of the user mayimply one or more items of information on a position of the user as awhole and/or one of or more body parts of the user. Thus, preferably,the position of the user may imply one or more items of information on aposition of the user as provided by the evaluation device of thedetector. The user, a body part of the user or a plurality of body partsof the user may be regarded as one or more objects the position of whichmay be detected by the at least one detector device. Therein, preciselyone detector may be provided, or a combination of a plurality ofdetectors may be provided. As an example, a plurality of detectors maybe provided for determining positions of a plurality of body parts ofthe user and/or for determining a position of at least one body part ofthe user.

The detector according to the present invention, comprising the at leastone optical sensor and the at least one evaluation device, may furtherbe combined with one or more other types of sensors or detectors. Thus,the detector comprising the at least one optical sensor having thematrix of pixels (in the following also simply referred to as thepixelated optical sensor and/or the pixelated sensor) and the at leastone evaluation device may further comprise at least one additionaldetector. The at least one additional detector may be adapted fordetecting at least one parameter, such as at least one of: a parameterof a surrounding environment, such as a temperature and/or a brightnessof a surrounding environment; a parameter regarding a position and/ororientation of the detector; a parameter specifying a state of theobject to be detected, such as a position of the object, e.g. anabsolute position of the object and/or an orientation of the object inspace. Thus, generally, the principles of the present invention may becombined with other measurement principles in order to gain additionalinformation and/or in order to verify measurement results or reducemeasurement errors or noise.

Specifically, the detector according to the present invention mayfurther comprise at least one time-of-flight (ToF) detector adapted fordetecting at least one distance between the at least one object and thedetector by performing at least one time-of-flight measurement. As usedherein, a time-of-flight measurement generally refers to a measurementbased on a time a signal needs for propagating between two objects orfrom one object to a second object and back. In the present case, thesignal specifically may be one or more of an acoustic signal or anelectromagnetic signal such as a light signal. A time-of-flight detectorconsequently refers to a detector adapted for performing atime-of-flight measurement. Time-of-flight measurements are well-knownin various fields of technology such as in commercially availabledistance measurement devices or in commercially available flow meters,such as ultrasonic flow meters. Time-of-flight detectors even may beembodied as time-of-flight cameras. These types of cameras arecommercially available as range-imaging camera systems, capable ofresolving distances between objects based on the known speed of light.

Presently available ToF detectors generally are based on the use of apulsed signal, optionally in combination with one or more light sensorssuch as CMOS-sensors. A sensor signal produced by the light sensor maybe integrated. The integration may start at two different points intime. The distance may be calculated from the relative signal intensitybetween the two integration results.

Further, as outlined above, ToF cameras are known and may generally beused, also in the context of the present invention. These ToF camerasmay contain pixelated light sensors. However, since each pixel generallyhas to allow for performing two integrations, the pixel constructiongenerally is more complex and the resolutions of commercially availableToF cameras is rather low (typically 200×200 pixels). Distances below˜40 cm and above several meters typically are difficult or impossible todetect. Furthermore, the periodicity of the pulses leads to ambiguousdistances, as only the relative shift of the pulses within one period ismeasured.

ToF detectors, as standalone devices, typically suffer from a variety ofshortcomings and technical challenges. Thus, in general, ToF detectorsand, more specifically, ToF cameras suffer from rain and othertransparent objects in the light path, since the pulses might bereflected too early, objects behind the raindrop are hidden, or inpartial reflections the integration will lead to erroneous results.Further, in order to avoid errors in the measurements and in order toallow for a clear distinction of the pulses, low light conditions arepreferred for ToF-measurements. Bright light such as bright sunlight canmake a ToF-measurement impossible. Further, the energy consumption oftypical ToF cameras is rather high, since pulses must be bright enoughto be back-reflected and still be detectable by the camera. Thebrightness of the pulses, however, may be harmful for eyes or othersensors or may cause measurement errors when two or more ToFmeasurements interfere with each other. In summary, current ToFdetectors and, specifically, current ToF-cameras suffer from severaldisadvantages such as low resolution, ambiguities in the distancemeasurement, limited range of use, limited light conditions, sensitivitytowards transparent objects in the light path, sensitivity towardsweather conditions and high energy consumption. These technicalchallenges generally lower the aptitude of present ToF cameras for dailyapplications such as for safety applications in cars, cameras for dailyuse or human-machine-interfaces, specifically for use in gamingapplications.

In combination with the detector according to the present invention,having the at least one optical sensor comprising the matrix of pixelsand as well as the above-mentioned principle of evaluating the number ofilluminated pixels, the advantages and capabilities of both systems maybe combined in a fruitful way. Thus, the detector may provide advantagesat bright light conditions, while the ToF detector generally providesbetter results at low-light conditions. A combined device, i.e. adetector according to the present invention further including at leastone ToF detector, therefore provides increased tolerance with regard tolight conditions as compared to both single systems. This is especiallyimportant for safety applications, such as in cars or other vehicles.

Specifically, the detector may be designed to use at least one ToFmeasurement for correcting at least one measurement performed by usingthe detector according to the present invention and vice versa. Further,the ambiguity of a ToF measurement may be resolved by using thedetector. A measurement using the pixelated detector specifically may beperformed whenever an analysis of ToF measurements results in alikelihood of ambiguity. Additionally or alternatively, measurementsusing the pixelated detector may be performed continuously in order toextend the working range of the ToF detector into regions which areusually excluded due to the ambiguity of ToF measurements. Additionallyor alternatively, the pixelated detector may cover a broader or anadditional range to allow for a broader distance measurement region. Thepixelated detector, specifically the pixelated camera, may further beused for determining one or more important regions for measurements toreduce energy consumption or to protect eyes. Thus the pixelateddetector may be adapted for detecting one or more regions of interest.Additionally or alternatively, the pixelated detector may be used fordetermining a rough depth map of one or more objects within a scenecaptured by the detector, wherein the rough depth map may be refined inimportant regions by one or more ToF measurements. Further, thepixelated detector may be used to adjust the ToF detector, such as theToF camera, to the required distance region. Thereby, a pulse lengthand/or a frequency of the ToF measurements may be pre-set, such as forremoving or reducing the likelihood of ambiguities in the ToFmeasurements. Thus, generally, the pixelated detector may be used forproviding an autofocus for the ToF detector, such as for the ToF camera.

As outlined above, a rough depth map may be recorded by the pixelateddetector, such as the pixelated camera. Further, the rough depth map,containing depth information or z-information regarding one or moreobjects within a scene captured by the detector, may be refined by usingone or more ToF measurements. The ToF measurements specifically may beperformed only in important regions. Additionally or alternatively, therough depth map may be used to adjust the ToF detector, specifically theToF camera.

Further, the use of the pixelated detector in combination with the atleast one ToF detector may solve the above-mentioned problem of thesensitivity of ToF detectors towards the nature of the object to bedetected or towards obstacles or media within the light path between thedetector and the object to be detected, such as the sensitivity towardsrain or weather conditions. A combined pixelated/ToF measurement may beused to extract the important information from ToF signals, or measurecomplex objects with several transparent or semi-transparent layers.Thus, objects made of glass, crystals, liquid structures, phasetransitions, liquid motions, etc. may be observed. Further, thecombination of a pixelated detector and at least one ToF detector willstill work in rainy weather, and the overall detector will generally beless dependent on weather conditions. As an example, measurement resultsprovided by the pixelated detector may be used to remove the errorsprovoked by rain from ToF measurement results, which specificallyrenders this combination useful for safety applications such as in carsor other vehicles.

The implementation of at least one ToF detector into the detectoraccording to the present invention may be realized in various ways.Thus, the at least one pixelated detector and the at least one ToFdetector may be arranged in a sequence, within the same light path. Asan example, at least one transparent pixelated detector may be placed infront of at least one ToF detector. Additionally or alternatively,separate light paths or split light paths for the pixelated detector andthe ToF detector may be used. Therein, as an example, light paths may beseparated by one or more beam-splitting elements, such as one or more ofthe beam splitting elements listed above or listed in further detailbelow. As an example, a separation of beam paths by wavelength-selectiveelements may be performed. Thus, e.g., the ToF detector may make use ofinfrared light, whereas the pixelated detector may make use of light ofa different wavelength. In this example, the infrared light for the ToFdetector may be separated off by using a wavelength-selective beamsplitting element such as a hot mirror. Additionally or alternatively,light beams used for the measurement using the pixelated detector andlight beams used for the ToF measurement may be separated by one or morebeam-splitting elements, such as one or more semitransparent mirrors,beam-splitter cubes, polarization beam splitters or combinationsthereof. Further, the at least one pixelated detector and the at leastone ToF detector may be placed next to each other in the same device,using distinct optical pathways. Various other setups are feasible.

The at least one optional ToF detector may be combined with basicallyany of the embodiments of the detector according to the presentinvention. Specifically, the at least one ToF detector which may be asingle ToF detector or a ToF camera, may be combined with a singleoptical sensor or with a plurality of optical sensors such as a sensorstack. Further, the detector may also comprise one or more imagingdevices such as one or more inorganic imaging devices like CCD chipsand/or CMOS chips, preferably one or more full-color CCD chips orfull-color CMOS chips. Additionally or alternatively, the detector mayfurther comprise one or more thermographic cameras.

As outlined above, the human-machine interface may comprise a pluralityof beacon devices which are adapted to be at least one of directly orindirectly attached to the user and held by the user. Thus, the beacondevices each may independently be attached to the user by any suitablemeans, such as by an appropriate fixing device. Additionally oralternatively, the user may hold and/or carry the at least one beacondevice or one or more of the beacon devices in his or her hands and/orby wearing the at least one beacon device and/or a garment containingthe beacon device on a body part.

The beacon device generally may be an arbitrary device which may bedetected by the at least one detector and/or which facilitates detectionby the at least one detector. Thus, as outlined above or as will beoutlined in further detail below, the beacon device may be an activebeacon device adapted for generating the at least one light beam to bedetected by the detector, such as by having one or more illuminationsources for generating the at least one light beam. Additionally oralternatively, the beacon device may fully or partially be designed as apassive beacon device, such as by providing one or more reflectiveelements adapted to reflect a light beam generated by a separateillumination source. The at least one beacon device may permanently ortemporarily be attached to the user in a direct or indirect way and/ormay be carried or held by the user. The attachment may take place byusing one or more attachment means and/or by the user himself orherself, such as by the user holding the at least one beacon device byhand and/or by the user wearing the beacon device.

Additionally or alternatively, the beacon devices may be at least one ofattached to an object and integrated into an object held by the user,which, in the sense of the present invention, shall be included into themeaning of the option of the user holding the beacon devices. Thus, aswill be outlined in further detail below, the beacon devices may beattached to or integrated into a control element which may be part ofthe human-machine interface and which may be held or carried by theuser, and of which the orientation may be recognized by the detectordevice. Thus, generally, the present invention also refers to a detectorsystem comprising at least one detector device according to the presentinvention and which, further, may comprise at least one object, whereinthe beacon devices are one of attached to the object, held by the objectand integrated into the object. As an example, the object preferably mayform a control element, the orientation of which may be recognized by auser. Thus, the detector system may be part of the human-machineinterface as outlined above or as outlined in further detail below. Asan example, the user may handle the control element in a specific way inorder to transmit one or more items of information to a machine, such asin order to transmit one or more commands to the machine.

Alternatively, the detector system may be used in other ways. Thus, asan example, the object of the detector system may be different from auser or a body part of the user and, as an example, may be an objectwhich moves independently from the user. As an example, the detectorsystem may be used for controlling apparatuses and/or industrialprocesses, such as manufacturing processes and/or robotics processes.Thus, as an example, the object may be a machine and/or a machine part,such as a robot arm, the orientation of which may be detected by usingthe detector system.

The human-machine interface may be adapted in such a way that thedetector device generates at least one item of information on theposition of the user or of at least one body part of the user.Specifically in case a manner of attachment of the at least one beacondevice to the user is known, by evaluating the position of the at leastone beacon device, at least one item of information on a position and/oran orientation of the user or of a body part of the user may be gained.

The beacon device preferably is one of a beacon device attachable to abody or a body part of the user and a beacon device which may be held bythe user. As outlined above, the beacon device may fully or partially bedesigned as an active beacon device. Thus, the beacon device maycomprise at least one illumination source adapted to generate at leastone light beam to be transmitted to the detector, preferably at leastone light beam having known beam properties. Additionally oralternatively, the beacon device may comprise at least one reflectoradapted to reflect light generated by an illumination source, therebygenerating a reflected light beam to be transmitted to the detector.

The object, which may form part of the detector system, may generallyhave an arbitrary shape. Preferably, the object being part of thedetector system, as outlined above, may be a control element which maybe handled by a user, such as manually. As an example, the controlelement may be or may comprise at least one element selected from thegroup consisting of: a glove, a jacket, a hat, shoes, trousers and asuit; a stick that may be held by hand; a bat; a club; a racket; a cane;a toy, such as a toy gun. Thus, as an example, the detector system maybe part of the human-machine interface and/or of the entertainmentdevice.

As used herein, an entertainment device is a device which may serve thepurpose of leisure and/or entertainment of one or more users, in thefollowing also referred to as one or more players. As an example, theentertainment device may serve the purpose of gaming, preferablycomputer gaming. Thus, the entertainment device may be implemented intoa computer, a computer network or a computer system or may comprise acomputer, a computer network or a computer system which runs one or moregaming software programs.

The entertainment device comprises at least one human-machine interfaceaccording to the present invention, such as according to one or more ofthe embodiments disclosed above and/or according to one or more of theembodiments disclosed below. The entertainment device is designed toenable at least one item of information to be input by a player by meansof the human-machine interface. The at least one item of information maybe transmitted to and/or may be used by a controller and/or a computerof the entertainment device.

The at least one item of information preferably may comprise at leastone command adapted for influencing the course of a game. Thus, as anexample, the at least one item of information may include at least oneitem of information on at least one orientation of the player and/or ofone or more body parts of the player, thereby allowing for the player tosimulate a specific position and/or orientation and/or action requiredfor gaming. As an example, one or more of the following movements may besimulated and communicated to a controller and/or a computer of theentertainment device: dancing; running; jumping; swinging of a racket;swinging of a bat; swinging of a club; pointing of an object towardsanother object, such as pointing of a toy gun towards a target.

The entertainment device as a part or as a whole, preferably acontroller and/or a computer of the entertainment device, is designed tovary the entertainment function in accordance with the information.Thus, as outlined above, a course of a game might be influenced inaccordance with the at least one item of information. Thus, theentertainment device might include one or more controllers which mightbe separate from the evaluation device of the at least one detectorand/or which might be fully or partially identical to the at least oneevaluation device or which might even include the at least oneevaluation device. Preferably, the at least one controller might includeone or more data processing devices, such as one or more computersand/or microcontrollers.

As further used herein, a tracking system is a device which is adaptedto gather information on a series of past positions of the at least oneobject and/or at least one part of the object. Additionally, thetracking system may be adapted to provide information on at least onepredicted future position and/or orientation of the at least one objector the at least one part of the object. The tracking system may have atleast one track controller, which may fully or partially be embodied asan electronic device, preferably as at least one data processing device,more preferably as at least one computer or microcontroller. Again, theat least one track controller may fully or partially comprise the atleast one evaluation device and/or may be part of the at least oneevaluation device and/or may fully or partially be identical to the atleast one evaluation device.

The tracking system comprises at least one detector according to thepresent invention, such as at least one detector as disclosed in one ormore of the embodiments listed above and/or as disclosed in one or moreof the embodiments below. The tracking system further comprises at leastone track controller. The track controller is adapted to track a seriesof positions of the object at specific points in time, such as byrecording groups of data or data pairs, each group of data or data paircomprising at least one position information and at least one timeinformation.

The tracking system may further comprise the at least one detectorsystem according to the present invention. Thus, besides the at leastone detector and the at least one evaluation device and the optional atleast one beacon device, the tracking system may further comprise theobject itself or a part of the object, such as at least one controlelement comprising the beacon devices or at least one beacon device,wherein the control element is directly or indirectly attachable to orintegratable into the object to be tracked.

The tracking system may be adapted to initiate one or more actions ofthe tracking system itself and/or of one or more separate devices. Forthe latter purpose, the tracking system, preferably the trackcontroller, may have one or more wireless and/or wire-bound interfacesand/or other types of control connections for initiating at least oneaction. Preferably, the at least one track controller may be adapted toinitiate at least one action in accordance with at least one actualposition of the object. As an example, the action may be selected fromthe group consisting of: a prediction of a future position of theobject; pointing at least one device towards the object; pointing atleast one device towards the detector; illuminating the object;illuminating the detector.

As an example of application of a tracking system, the tracking systemmay be used for continuously pointing at least one first object to atleast one second object even though the first object and/or the secondobject might move. Potential examples, again, may be found in industrialapplications, such as in robotics and/or for continuously working on anarticle even though the article is moving, such as during manufacturingin a manufacturing line or assembly line. Additionally or alternatively,the tracking system might be used for illumination purposes, such as forcontinuously illuminating the object by continuously pointing anillumination source to the object even though the object might bemoving. Further applications might be found in communication systems,such as in order to continuously transmit information to a moving objectby pointing a transmitter towards the moving object.

The optional transfer device can, as explained above, be designed tofeed light propagating from the object to the detector to the opticalsensor, preferably successively. As explained above, this feeding canoptionally be effected by means of imaging or else by means ofnon-imaging properties of the transfer device. In particular thetransfer device can also be designed to collect the electromagneticradiation before the latter is fed to the optical sensor. The optionaltransfer device can also, as explained in even greater detail below, bewholly or partly a constituent part of at least one optionalillumination source, for example by the illumination source beingdesigned to provide a light beam having defined optical properties, forexample having a defined or precisely known beam profile, for example atleast one Gaussian beam, in particular at least one laser beam having aknown beam profile.

For potential embodiments of the optional illumination source, referencemay be made to WO 2012/110924 A1. Still, other embodiments are feasible.Light emerging from the object can originate in the object itself, butcan also optionally have a different origin and propagate from thisorigin to the object and subsequently toward the transversal and/orlongitudinal optical sensor. The latter case can be effected for exampleby at least one illumination source being used. This illumination sourcecan for example be or comprise an ambient illumination source and/or maybe or may comprise an artificial illumination source. By way of example,the detector itself can comprise at least one illumination source, forexample at least one laser and/or at least one incandescent lamp and/orat least one semiconductor illumination source, for example, at leastone light-emitting diode, in particular an organic and/or inorganiclight-emitting diode. On account of their generally defined beamprofiles and other properties of handleability, the use of one or aplurality of lasers as illumination source or as part thereof, isparticularly preferred. The illumination source itself can be aconstituent part of the detector or else be formed independently of thedetector. The illumination source can be integrated in particular intothe detector, for example a housing of the detector. Alternatively oradditionally, at least one illumination source can also be integratedinto the at least one beacon device or into one or more of the beacondevices and/or into the object or connected or spatially coupled to theobject.

The light emerging from the beacon devices can accordingly,alternatively or additionally from the option that said light originatesin the respective beacon device itself, emerge from the illuminationsource and/or be excited by the illumination source. By way of example,the electromagnetic light emerging from the beacon device can be emittedby the beacon device itself and/or be reflected by the beacon deviceand/or be scattered by the beacon device before it is fed to thedetector. In this case, emission and/or scattering of theelectromagnetic radiation can be effected without spectral influencingof the electromagnetic radiation or with such influencing. Thus, by wayof example, a wavelength shift can also occur during scattering, forexample according to Stokes or Raman. Furthermore, emission of light canbe excited, for example, by a primary illumination source, for exampleby the object or a partial region of the object being excited togenerate luminescence, in particular phosphorescence and/orfluorescence. Other emission processes are also possible, in principle.If a reflection occurs, then the object can have for example at leastone reflective region, in particular at least one reflective surface.Said reflective surface can be a part of the object itself, but can alsobe for example a reflector which is connected or spatially coupled tothe object, for example a reflector plaque connected to the object. Ifat least one reflector is used, then it can in turn also be regarded aspart of the detector which is connected to the object, for example,independently of other constituent parts of the detector.

The beacon devices and/or the at least one optional illumination sourceindependently from each other and generally may emit light in at leastone of: the ultraviolet spectral range, preferably in the range of 200nm to 380 nm; the visible spectral range (380 nm to 780 nm); theinfrared spectral range, preferably in the range of 780 nm to 3.0micrometers. Most preferably, the at least one illumination source isadapted to emit light in the visible spectral range, preferably in therange of 500 nm to 780 nm, most preferably at 650 nm to 750 nm or at 690nm to 700 nm.

The feeding of the light beam to the optical sensor can be effected inparticular in such a way that a light spot, for example having a round,oval or differently configured cross section, is produced on theoptional sensor area of the optical sensor. By way of example, thedetector can have a visual range, in particular a solid angle rangeand/or spatial range, within which objects can be detected. Preferably,the optional transfer device is designed in such a way that the lightspot, for example in the case of an object arranged within a visualrange of the detector, is arranged completely on a sensor region and/oron a sensor area of the optical sensor. By way of example, a sensor areacan be chosen to have a corresponding size in order to ensure thiscondition.

The evaluation device can comprise in particular at least one dataprocessing device, in particular an electronic data processing device,which can be designed to generate the at least one item of informationon the position of the object. Thus, the evaluation device may bedesigned to use the number of illuminated pixels of the optical sensoror of each optical sensor as input variables and to generate the atleast one item of information on the position of the object byprocessing these input variables. The processing can be done inparallel, subsequently or even in a combined manner. The evaluationdevice may use an arbitrary process for generating these items ofinformation, such as by calculation and/or using at least one storedand/or known relationship. The relationship can be a predeterminedanalytical relationship or can be determined or determinableempirically, analytically or else semi-empirically. Particularlypreferably, the relationship comprises at least one calibration curve,at least one set of calibration curves, at least one function or acombination of the possibilities mentioned. One or a plurality ofcalibration curves can be stored for example in the form of a set ofvalues and the associated function values thereof, for example in a datastorage device and/or a table. Alternatively or additionally, however,the at least one calibration curve can also be stored for example inparameterized form and/or as a functional equation.

By way of example, the evaluation device can be designed in terms ofprogramming for the purpose of determining the items of information. Theevaluation device can comprise in particular at least one computer, forexample at least one microcomputer. Furthermore, the evaluation devicecan comprise one or a plurality of volatile or nonvolatile datamemories. As an alternative or in addition to a data processing device,in particular at least one computer, the evaluation device can compriseone or a plurality of further electronic components which are designedfor determining the items of information, for example an electronictable and in particular at least one look-up table and/or at least oneapplication-specific integrated circuit (ASIC).

Overall, in the context of the present invention, the followingembodiments are regarded as preferred:

Embodiment 1

A detector for determining a position of at least one object, thedetector comprising:

-   -   at least one optical sensor, the optical sensor being adapted to        detect a light beam traveling from the object towards the        detector, the optical sensor having at least one matrix of        pixels; and    -   at least one evaluation device, the evaluation device being        adapted for determining an intensity distribution of pixels of        the optical sensor which are illuminated by the light beam, the        evaluation device further being adapted for determining at least        one longitudinal coordinate of the object by using the intensity        distribution.

Embodiment 2

The detector according to the preceding embodiment, wherein theevaluation device is adapted to determine the longitudinal coordinate ofthe object by using a predetermined relationship between the intensitydistribution and the longitudinal coordinate.

Embodiment 3

The detector according to any one of the preceding embodiments, whereinthe intensity distribution comprises one or more of:

-   -   an intensity as a function of a transversal position of the        respective pixel in a plane perpendicular to an optical axis of        the optical sensor;    -   an intensity as a function of a pixel coordinate;    -   a distribution of a number # of pixels having a specific        intensity as a function of the intensity.

Embodiment 4

The detector according to any one of the preceding embodiments, whereinthe intensity distribution approximates an intensity distribution of anillumination by a Gaussian light beam.

Embodiment 5

The detector according to any one of the preceding embodiments, whereinthe evaluation device is adapted to determine at least one intensitydistribution function approximating the intensity distribution.

Embodiment 6

The detector according to the preceding embodiment, wherein theevaluation device is adapted to determine the longitudinal coordinate ofthe object by using a predetermined relationship between a longitudinalcoordinate and the intensity distribution function and/or at least oneparameter derived from the intensity distribution function.

Embodiment 7

The detector according to any one of the two preceding embodiments,wherein the intensity distribution function is a beam shape function ofthe light beam.

Embodiment 8

The detector according to any one of the three preceding embodiments,wherein the intensity distribution function comprises a two-dimensionalor a three-dimensional mathematical function approximating an intensityinformation contained within at least part of the pixels of the opticalsensor.

Embodiment 9

The detector according to the preceding embodiment, wherein thetwo-dimensional or three-dimensional mathematical function comprises afunction of at least one pixel coordinate of the matrix of pixels.

Embodiment 10

The detector according to any one of the two preceding embodiments,wherein a pixel position of the pixels of the matrix is defined by (x,y), with x, y being pixel coordinates, wherein the two-dimensional orthree-dimensional mathematical function comprises one or more functionsselected from the group consisting of f(x), f(y), f(x, y).

Embodiment 11

The detector according to any one of the three preceding embodiments,wherein the two-dimensional or three-dimensional mathematical functionis selected from the group consisting of: a bell-shaped function; aGaussian distribution function; a Bessel function; a Hermite-Gaussianfunction; a Laguerre-Gaussian function; a Lorentz distribution function;a binomial distribution function; a Poisson distribution function.

Embodiment 12

The detector according to any one of the preceding embodiments, whereinthe detector is adapted to determine intensity distributions in aplurality of planes, preferably adapted to determine intensitydistribution for each of the planes, wherein the planes preferably areperpendicular to an optical axis of the detector, and wherein preferablythe plurality of planes are offset from one another along the opticalaxis.

Embodiment 13

The detector according to the preceding embodiment, wherein the detectorcomprises a plurality of optical sensors, specifically a stack ofoptical sensors.

Embodiment 14

The detector according to any one of the two preceding embodiments,wherein the evaluation device is adapted to evaluate a change in theintensity distribution as a function of a longitudinal coordinate alongthe optical axis for determining the longitudinal coordinate of theobject.

Embodiment 15

The detector according to any one of the three preceding embodiments,wherein the evaluation device is adapted to determine a plurality ofintensity distribution functions, each intensity distribution functionapproximating the intensity distribution in one of the planes, whereinthe evaluation device is further adapted to derive the longitudinalcoordinate of the object from the plurality of intensity distributionfunctions.

Embodiment 16

The detector according to the preceding embodiment, wherein each of theintensity distribution functions is a beam shape function of the lightbeam in the respective plane.

Embodiment 17

The detector according to any one of the two preceding embodiments,wherein the evaluation device is adapted to derive at least one beamparameter from each intensity distribution function.

Embodiment 18

The detector according to the preceding embodiment, wherein theevaluation device is adapted to evaluate a change of the at least onebeam parameter as a function of a longitudinal coordinate along theoptical axis for determining the longitudinal coordinate of the object.

Embodiment 19

The detector according to any one of the two preceding embodiments,wherein the at least one beam parameter is selected from the groupconsisting of: a beam diameter; a beam waist; a Gaussian beam parameter.

Embodiment 20

The detector according to any one of the three preceding embodiments,wherein the evaluation device is adapted to determine the longitudinalcoordinate of the object by using a predetermined relationship betweenthe beam parameters and the longitudinal coordinate.

Embodiment 20

The detector according to any one of the preceding embodiments, whereinthe optical sensor is adapted to generate at least one signal indicatingan intensity of illumination for each of the pixels.

Embodiment 21

The detector according to any one of the nine preceding embodiments,wherein the evaluation device is adapted to compare, for each of thepixels, the signal to at least one threshold in order to determinewhether the pixel is an illuminated pixel or not.

Embodiment 22

The detector according to the preceding embodiment, wherein theevaluation device is adapted to determine at least one pixel having thehighest illumination out of the pixels by comparing the signals of thepixels.

Embodiment 23

The detector according to the preceding embodiment, wherein theevaluation device is further adapted to choose the threshold as afraction of the signal of the at least one pixel having the highestillumination.

Embodiment 24

The detector according to the preceding embodiment, wherein theevaluation device is adapted to choose the threshold by multiplying thesignal of the at least one pixel having the highest illumination with afactor of 1/e².

Embodiment 25

The detector according to any one of the preceding embodiments, whereinthe determining of the intensity distribution comprises determining anumber N of pixels of the optical sensor which are illuminated by thelight beam, wherein the determining of the at least one longitudinalcoordinate of the object comprises using the number N of pixels whichare illuminated by the light beam.

Embodiment 26

The detector according to the preceding embodiment, wherein theevaluation device is adapted to determine the longitudinal coordinate ofthe object by using a predetermined relationship between the number N ofpixels which are illuminated by the light beam and the longitudinalcoordinate.

Embodiment 27

The detector according to the preceding embodiment, wherein thepredetermined relationship is based on the assumption of the light beambeing a Gaussian light beam.

Embodiment 28

The detector according to any one of the two preceding embodiments,wherein the predetermined relationship is

${N \sim {\pi \cdot w_{0}^{2} \cdot \left( {1 + \left( \frac{z}{z_{0}} \right)^{2}} \right)}},$

-   -   wherein z is the longitudinal coordinate,    -   wherein w₀ is a minimum beam radius of the light beam when        propagating in space,    -   wherein z₀ is a Rayleigh-length of the light beam with z₀=π·w₀        ²/λ, λ being the wavelength of the light beam.

Embodiment 29

The detector according to any one of the preceding embodiments, whereinthe matrix of pixels is a two-dimensional matrix.

Embodiment 30

The detector according to any one of the preceding embodiments, whereinthe matrix of pixels is a rectangular matrix.

Embodiment 31

The detector according to any one of the preceding embodiments, whereinthe detector comprises a plurality of the optical sensors.

Embodiment 32

The detector according to the preceding embodiment, wherein the opticalsensors are stacked along an optical axis of the detector.

Embodiment 33

The detector according to any one of the two preceding embodiments,wherein the detector comprises n optical sensors, wherein n preferablyis a positive integer, wherein the evaluation device is adapted todetermine a number N_(i) of pixels which are illuminated by the lightbeam for each of the optical sensors, wherein i∈{1, n} denotes therespective optical sensor.

Embodiment 34

The detector according to any one of the three preceding embodiments,wherein the evaluation device is adapted to compare the number N_(i) ofpixels which are illuminated by the light beam for each optical sensorwith at least one neighboring optical sensor, thereby resolving anambiguity in the longitudinal coordinate of the object.

Embodiment 36

The detector according to any one of the four preceding embodiments,wherein the evaluation device is adapted to normalize sensor signals ofthe optical sensors for a power of the light beam.

Embodiment 37

The detector according to any one of the five preceding embodiments,wherein at least one of the optical sensors is transparent.

Embodiment 38

The detector according to any one of the six preceding embodiments,wherein at least two of the optical sensors have a differing spectralsensitivity, wherein the evaluation device is adapted to determine acolor of the light beam by comparing sensor signals of the opticalsensors having the differing spectral sensitivity.

Embodiment 39

The detector according to any one of the preceding embodiments, whereinthe evaluation device is further adapted to determine at least onetransversal coordinate of the object by determining a position of thelight beam on the matrix of pixels.

Embodiment 40

The detector according to the preceding embodiment, wherein theevaluation device is adapted to determine a center of illumination ofthe matrix by the light beam, wherein the at least one transversalcoordinate of the object is determined by evaluating at least onecoordinate of the center of illumination.

Embodiment 41

The detector according to the preceding embodiment, wherein thecoordinate of the center of illumination is a pixel coordinate of thecenter of illumination.

Embodiment 42

The detector according to any one of the three preceding embodiments,wherein the evaluation device is adapted to provide at least onethree-dimensional position of the object.

Embodiment 43

The detector according to any one of the three preceding embodiments,wherein the evaluation device is adapted to provide at least onethree-dimensional image of a scene captured by the detector.

Embodiment 44

The detector according to any one of the preceding embodiments, whereinthe detector further comprises at least one transfer device, thetransfer device being adapted to guide the light beam onto the opticalsensor.

Embodiment 45

The detector according to the preceding embodiment, wherein the transferdevice has imaging properties.

Embodiment 46

The detector according to any one of the two preceding embodiments,wherein the transfer device comprises at least one element selected fromthe group consisting of a lens, a mirror, a prism, awavelength-selective element; a diaphragm.

Embodiment 47

The detector according to any one of the preceding embodiments, whereinthe optical sensor comprises at least one organic photovoltaic device.

Embodiment 48

The detector according to any one of the preceding embodiments, whereinthe optical sensor comprises at least one dye-sensitized solar cellhaving at least one patterned electrode.

Embodiment 49

The detector according to any one of the preceding embodiments, whereinthe optical sensor comprises at least one first electrode, at least onesecond electrode and at least one light-sensitive layer embedded inbetween the first electrode and the second electrode.

Embodiment 50

The detector according to the preceding embodiment, wherein the firstelectrode comprises a plurality of first electrode stripes and whereinthe second electrode comprises a plurality of second electrode stripes,wherein the first electrode stripes are oriented perpendicular to thesecond electrode stripes.

Embodiment 51

The detector according to any one of the preceding embodiments, whereinthe optical sensor comprises at least one first electrode, at least onen-semiconducting metal oxide, at least one dye, at least onep-semiconducting organic material, preferably a solid p-semiconductingorganic material, and at least one second electrode, with the at leastone n-semiconducting metal oxide, the at least one dye and the at leastone p-semiconducting organic material being embedded in between thefirst electrode and the second electrode.

Embodiment 52

The detector according to the preceding embodiment, wherein both thefirst electrode and the second electrode are transparent.

Embodiment 53

The detector according to any one of the two preceding embodiments,wherein at least one of the first electrode and the second electrode isthe patterned electrode.

Embodiment 54

The detector according to any one of the three preceding embodiments,wherein the first electrode comprises a plurality of first electrodestripes and wherein the second electrode comprises a plurality of secondelectrode stripes, wherein the first electrode stripes are orientedperpendicular to the second electrode stripes.

Embodiment 55

The detector according to any one of the four preceding embodiments,wherein at least one of the first electrode and the second electrodecomprise an electrically conductive polymer.

Embodiment 56

The detector according to any one of the preceding embodiments, whereinthe detector comprises at least one stack of the optical sensors,wherein the detector is adapted to acquire a three-dimensional image ofa scene within a field of view of the detector.

Embodiment 57

The detector according to the preceding embodiment, wherein the opticalsensors of the stack have differing spectral properties.

Embodiment 58

The detector according to the preceding embodiment, wherein the stackcomprises at least one first optical sensor having a first spectralsensitivity and at least one second optical sensor having a secondspectral sensitivity, wherein the first spectral sensitivity and thesecond spectral sensitivity are different.

Embodiment 59

The detector according to any one of the two preceding embodiments,wherein the stack comprises optical sensors having differing spectralproperties in an alternating sequence.

Embodiment 60

The detector according to any one of the three preceding embodiments,wherein the detector is adapted to acquire a multicolorthree-dimensional image, preferably a full-color three-dimensionalimage, by evaluating sensor signals of the optical sensors havingdiffering spectral properties.

Embodiment 61

The detector according to any one of the preceding embodiments, whereinthe detector further comprises at least one time-of-flight detectoradapted for detecting at least one distance between the at least oneobject and the detector by performing at least one time-of-flightmeasurement.

Embodiment 62

The detector according to any one of the preceding embodiments, whereinthe at least one optical sensor comprises at least one optical sensorhaving at least one sensor region and being capable of providing atleast one sensor signal, wherein the sensor signal, given the same totalpower of illumination of the sensor region by the light beam, isdependent on a geometry of the illumination, in particular on a beamcross section of the illumination on the sensor area.

Embodiment 63

The detector according to any one of the preceding embodiments, whereinthe at least one optical sensor comprises at least one stack of opticalsensors, each optical sensor having at least one sensor region and beingcapable of providing at least one sensor signal, wherein the sensorsignal, given the same total power of illumination of the sensor regionby the light beam, is dependent on a geometry of the illumination, inparticular on a beam cross section of the illumination on the sensorarea, wherein the evaluation device is adapted to compare at least onesensor signal generated by at least one pixel of a first one of theoptical sensors with at least one sensor signal generated by at leastone pixel of a second one of the optical sensors.

Embodiment 64

A detector system for determining a position of at least one object, thedetector system comprising at least one detector according to any one ofthe preceding embodiments, the detector system further comprising atleast one beacon device adapted to direct at least one light beamtowards the detector, wherein the beacon device is at least one ofattachable to the object, holdable by the object and integratable intothe object.

Embodiment 65

The detector system according to the preceding embodiment, wherein thebeacon device comprises at least one illumination source.

Embodiment 66

The detector system according to any one of the two precedingembodiments, wherein the beacon device comprises at least one reflectivedevice adapted to reflect a primary light beam generated by anillumination source independent from the object.

Embodiment 67

The detector system according to any one of the three precedingembodiments, wherein the detector system comprises at least two beacondevices, preferably at least three beacon devices.

Embodiment 68

The detector system according to any one of the four precedingembodiments, wherein the detector system further comprises the at leastone object.

Embodiment 69

The detector system according to the preceding embodiment, wherein theobject is a rigid object.

Embodiment 70

The detector system according to any one of the two precedingembodiments, wherein the object is selected from the group consistingof: an article of sports equipment, preferably an article selected fromthe group consisting of a racket, a club, a bat; an article of clothing;a hat; a shoe.

Embodiment 71

A human-machine interface for exchanging at least one item ofinformation between a user and a machine, wherein the human-machineinterface comprises at least one detector system according to any one ofthe preceding embodiments referring to a detector system, wherein the atleast one beacon device is adapted to be at least one of directly orindirectly attached to the user and held by the user, wherein thehuman-machine interface is designed to determine at least one positionof the user by means of the detector system, wherein the human-machineinterface is designed to assign to the position at least one item ofinformation.

Embodiment 72

An entertainment device for carrying out at least one entertainmentfunction, wherein the entertainment device comprises at least onehuman-machine interface according to the preceding embodiment, whereinthe entertainment device is designed to enable at least one item ofinformation to be input by a player by means of the human-machineinterface, wherein the entertainment device is designed to vary theentertainment function in accordance with the information.

Embodiment 73

A tracking system for tracking a position of at least one movableobject, the tracking system comprising at least one detector systemaccording to any one of the preceding embodiments referring to adetector system, the tracking system further comprising at least onetrack controller, wherein the track controller is adapted to track aseries of positions of the object at specific points in time.

Embodiment 74

A camera for imaging at least one object, the camera comprising at leastone detector according to any one of the preceding embodiments referringto a detector.

Embodiment 75

A method for determining a position of at least one object, the methodcomprising the following steps:

-   -   at least one detection step, wherein at least one light beam        traveling from the object to a detector is detected by at least        one optical sensor of the detector, the at least one optical        sensor having at least one matrix of pixels; and    -   at least one evaluation step, wherein an intensity distribution        of pixels of the optical sensor is determined which are        illuminated by the light beam, wherein at least one longitudinal        coordinate of the object is determined by using the intensity        distribution.

Embodiment 76

The method according to the preceding embodiment, wherein thelongitudinal coordinate of the object is determined by using apredetermined relationship between the intensity distribution and thelongitudinal coordinate.

Embodiment 77

The method according to any one of the preceding embodiments referringto a method, wherein the intensity distribution comprises one or moreof:

-   -   an intensity as a function of a transversal position of the        respective pixel in a plane perpendicular to an optical axis of        the optical sensor;    -   an intensity as a function of a pixel coordinate;    -   a distribution of a number # of pixels having a specific        intensity as a function of the intensity.

Embodiment 78

The method according to any one of the preceding embodiments referringto a method, wherein the intensity distribution approximates anintensity distribution of an illumination by a Gaussian light beam.

Embodiment 79

The method according to any one of the preceding embodiments referringto a method, wherein at least one intensity distribution functionapproximating the intensity distribution is determined.

Embodiment 80

The method according to the preceding embodiment, wherein thelongitudinal coordinate of the object is determined by using apredetermined relationship between a longitudinal coordinate and theintensity distribution function and/or at least one parameter derivedfrom the intensity distribution function.

Embodiment 81

The method according to any one of the two preceding embodiments,wherein the intensity distribution function is a beam shape function ofthe light beam.

Embodiment 82

The method according to any one of the three preceding embodiments,wherein the intensity distribution comprises a two-dimensional or athree-dimensional mathematical function approximating an intensityinformation contained within at least part of the pixels of the opticalsensor.

Embodiment 83

The method according to the preceding embodiment, wherein thetwo-dimensional or three-dimensional mathematical function comprises afunction of at least one pixel coordinate of the matrix of pixels.

Embodiment 84

The method according to any one of the two preceding embodiments,wherein a pixel position of the pixels of the matrix is defined by (x,y), with x, y being pixel coordinates, wherein the two-dimensional orthree-dimensional mathematical function comprises one or more functionsselected from the group consisting of f(x), f(y), f(x, y).

Embodiment 85

The method according to any one of the three preceding embodiments,wherein the two-dimensional or three-dimensional mathematical functioncomprises at least one mathematical function selected from the groupconsisting of: a bell-shaped function; a Gaussian distribution function;a Bessel function; a Hermite-Gaussian function; a Laguerre-Gaussianfunction; a Lorentz distribution function; a binomial distributionfunction; a Poisson distribution function; or at least one derivative,at least one linear combination or at least one product comprising oneor more of the listed functions.

Embodiment 86

The method according to any one of the preceding embodiments referringto a method, wherein intensity distributions are determined in aplurality of planes, wherein preferably at least one intensitydistribution for each of the planes is determined, wherein the planespreferably are perpendicular to an optical axis of the detector, andwherein preferably the plurality of planes are offset from one anotheralong the optical axis.

Embodiment 87

The method according to the preceding embodiment, wherein the detectorcomprises a plurality of optical sensors, specifically a stack ofoptical sensors.

Embodiment 88

The method according to any one of the two preceding embodiments,wherein a change in the intensity distribution is determined as afunction of a longitudinal coordinate along the optical axis fordetermining the longitudinal coordinate of the object.

Embodiment 89

The method according to any one of the three preceding embodiments,wherein a plurality of intensity distribution functions is determined,each intensity distribution function approximating the intensitydistribution in one of the planes, wherein further the longitudinalcoordinate of the object is derived from the plurality of intensitydistribution functions.

Embodiment 90

The method according to the preceding embodiment, wherein each of theintensity distribution functions is a beam shape function of the lightbeam in the respective plane.

Embodiment 91

The method according to any one of the two preceding embodiments,wherein at least one beam parameter is derived from each intensitydistribution function.

Embodiment 92

The method according to the preceding embodiment, wherein a change ofthe at least one beam parameter is determined as a function of alongitudinal coordinate along the optical axis for determining thelongitudinal coordinate of the object.

Embodiment 93

The method according to any one of the two preceding embodiments,wherein the at least one beam parameter is selected from the groupconsisting of: a beam diameter; a beam waist; a Gaussian beam parameter.

Embodiment 94

The method according to any one of the three preceding embodiments,wherein the longitudinal coordinate of the object is determined by usinga predetermined relationship between the beam parameters and thelongitudinal coordinate.

Embodiment 95

The method according to any one of the preceding embodiments referringto a method, wherein the optical sensor generates at least one signalindicating an intensity of illumination for each of the pixels.

Embodiment 96

The method according to the preceding embodiment, wherein, in theevaluation step, for each of the pixels, the signal is compared to atleast one threshold in order to determine whether the pixel is anilluminated pixel or not.

Embodiment 97

The method according to the preceding embodiment, wherein, in theevaluation step, at least one pixel having the highest illumination outof the pixels is determined by comparing the signals of the pixels.

Embodiment 98

The method according to the preceding embodiment, wherein the thresholdis chosen as a fraction of the signal of the at least one pixel havingthe highest illumination.

Embodiment 99

The method according to the preceding embodiment, wherein the thresholdis chosen by multiplying the signal of the at least one pixel having thehighest illumination with a factor of 1/e².

Embodiment 100

The method according to any one of the preceding embodiments referringto a method, wherein the determining of the intensity distributioncomprises determining a number N of pixels of the optical sensor whichare illuminated by the light beam, wherein the determining of the atleast one longitudinal coordinate of the object comprises using thenumber N of pixels which are illuminated by the light beam.

Embodiment 101

The method according to the preceding embodiment, wherein thelongitudinal coordinate of the object is determined by using apredetermined relationship between the number N of pixels which areilluminated by the light beam and the longitudinal coordinate.

Embodiment 102

The method according to the preceding embodiment, wherein thepredetermined relationship is based on the assumption of the light beambeing a Gaussian light beam.

Embodiment 103

The method according to any one of the two preceding embodiments,wherein the predetermined relationship is

${N \sim {\pi \cdot w_{0}^{2} \cdot \left( {1 + \left( \frac{z}{z_{0}} \right)^{2}} \right)}},$

-   -   wherein z is the longitudinal coordinate,    -   wherein w₀ is a minimum beam radius of the light beam when        propagating in space,    -   wherein z₀ is a Rayleigh-length of the light beam with z₀=π·w₀        ²/λ, λ being the wavelength of the light beam.

Embodiment 104

The method according to any one of the preceding method embodiments,wherein the matrix of pixels is a two-dimensional matrix.

Embodiment 105

The method according to any one of the preceding method embodiments,wherein the matrix of pixels is a rectangular matrix.

Embodiment 106

The method according to any one of the preceding method embodiments,wherein the detector comprises a plurality of the optical sensors.

Embodiment 107

The method according to the preceding embodiment, wherein the opticalsensors are stacked along an optical axis of the detector.

Embodiment 108

The method according to any one of the two preceding embodiments,wherein the detector comprises n optical sensors, wherein the numberN_(i) of pixels which are illuminated by the light beam is determinedfor each of the optical sensors, wherein i∈{1, n} denotes the respectiveoptical sensor.

Embodiment 109

The method according to any one of the three preceding embodiments,wherein the number N_(i) of pixels which are illuminated by the lightbeam for each optical sensor is compared with at least one neighboringoptical sensor, thereby resolving an ambiguity in the longitudinalcoordinate of the object.

Embodiment 110

The method according to any one of the four preceding embodiments,wherein the sensor signals of the optical sensors are normalized for apower of the light beam.

Embodiment 111

A use of the detector according to any one of the preceding embodimentsrelating to a detector, for a purpose of use, selected from the groupconsisting of: a position measurement in traffic technology; anentertainment application; a security application; a safety application;a human-machine interface application; a tracking application; aphotography application; a use in combination with at least onetime-of-flight detector.

BRIEF DESCRIPTION OF THE FIGURES

Further optional details and features of the invention are evident fromthe description of preferred exemplary embodiments which follows inconjunction with the dependent claims. In this context, the particularfeatures may be implemented alone or with several in combination. Theinvention is not restricted to the exemplary embodiments. The exemplaryembodiments are shown schematically in the figures. Identical referencenumerals in the individual figures refer to identical elements orelements with identical function, or elements which correspond to oneanother with regard to their functions.

Specifically, in the figures:

FIG. 1 shows an exemplary embodiment of a detector, a detector system, ahuman-machine interface, an entertainment device and a tracking systemaccording to the present invention;

FIG. 2A shows an exemplary embodiment of a detector according to thepresent invention;

FIG. 2B shows an exemplary embodiment of determining a number N ofpixels of an optical sensor of the detector according to FIG. 2A;

FIGS. 3A and 3B show typical propagation properties of a Gaussian beam;

FIG. 3C shows spectral sensitivities of three optical sensor devices;

FIGS. 4A to 4C show various views of an optical sensor which may be usedin the detector according to the present invention;

FIG. 5 shows another embodiment of a detector, a camera and ofdetermining a position of an object;

FIG. 6 shows an embodiment of the detector to be used as a light-fieldcamera; and

FIG. 7 shows an exemplary arrangement of an implementation of atime-of-flight detector into the detector.

FIG. 8 shows a cut through a Gaussian beam measured by 16 pixels.

FIG. 9 shows a cut though two Gaussian beams measured by 16 pixels.

FIG. 10 shows a cut through a square-shaped object measured by 16pixels.

FIG. 11 shows an intensity distribution of the square-shaped object ofFIG. 10, when the square-shaped object is slightly out of focus.

FIG. 12 shows an intensity distribution of the square-shaped object ofFIG. 10, when the square-shaped object is out of focus, and its edgesare becoming blurred.

FIG. 13 shows an intensity distribution of the square-shaped object ofFIG. 10, when the square-shaped object is further out of focus, inducinga further blurring of the edges and an overall blurred shape of theintensity distribution.

EXEMPLARY EMBODIMENTS

FIG. 1 shows, in a highly schematic illustration, an exemplaryembodiment of a detector 110, having a plurality of optical sensors 112.The detector 110 specifically may be embodied as a camera 111 or may bepart of a camera 111. The camera 111 may be made for imaging,specifically for 3D imaging, and may be made for acquiring standstillimages and/or image sequences such as digital video clips. Otherembodiments are feasible. FIG. 1 further shows an embodiment of adetector system 114, which, besides the at least one detector 110,comprises one or more beacon devices 116, which, in this exemplaryembodiment, are attached and/or integrated into an object 118, theposition of which shall be detected by using the detector 110. FIG. 1further shows an exemplary embodiment of a human-machine interface 120,which comprises the at least one detector system 114, and, further, anentertainment device 122, which comprises the human-machine interface120. The figure further shows an embodiment of a tracking system 124 fortracking a position of the object 118, which comprises the detectorsystem 114. The components of the devices and systems shall be explainedin further detail in the following.

The detector 110, besides the one or more optical sensors 112, comprisesat least one evaluation device 126. The evaluation device 126 may beconnected to the optical sensors 112 by one or more connectors 128and/or one or more interfaces. Further, the connector 128 may compriseone or more drivers and/or one or more measurement devices forgenerating sensor signals, as will be explained with regard to FIGS. 2Aand 2B below. Further, instead of using the at least one optionalconnector 128, the evaluation device 126 may fully or partially beintegrated into the optical sensors 112 and/or into a housing 130 of thedetector 110. Additionally or alternatively, the evaluation device 126may fully or partially be designed as a separate device.

In this exemplary embodiment, the object 118, the position of which maybe detected, may be designed as an article of sports equipment and/ormay form a control element 132, the position of which may be manipulatedby a user 134. As an example, the object 118 may be or may comprise abat, a record, a club or any other article of sports equipment and/orfake sports equipment. Other types of objects 118 are possible. Further,the user 134 himself or herself may be considered as the object 118, theposition of which shall be detected.

As outlined above, the detector 110 comprises the plurality of opticalsensors 112. The optical sensors 112 may be located inside the housing130 of the detector 110. Further, at least one transfer device 136 maybe comprised, such as one or more optical systems, preferably comprisingone or more lenses 138. An opening 140 inside the housing 130, which,preferably, is located concentrically with regard to an optical axis 142of the detector 110, preferably defines a direction of view 144 of thedetector 110. A coordinate system 146 may be defined, in which adirection parallel or antiparallel to the optical axis 142 is defined asa longitudinal direction, whereas directions perpendicular to theoptical axis 142 may be defined as transversal directions. In thecoordinate system 146, symbolically depicted in FIG. 1, a longitudinaldirection is denoted by z, and transversal directions are denoted by xand y, respectively. Other types of coordinate systems 146 are feasible.

The detector 110 may comprise one or more of the optical sensors 112.Preferably, as depicted in FIG. 1, a plurality of optical sensors 112 iscomprised, which, more preferably, are stacked along the optical axis142, in order to form a sensor stack 148. In the embodiment shown inFIG. 1, five optical sensors 112 are depicted. It shall be noted,however, that embodiments having a different number of optical sensors112 are feasible.

The optical sensors 112 or, at least, the optical sensors 112 besidesthe optical sensor 112 facing away from the object 118, preferably aretransparent to light beams 150 traveling from the object 118 and/or oneor more of the beacon devices 116 towards the detector 110, such thatthe at least one light beam 150 sequentially passes the optical sensors112.

The detector 110 is adapted for determining a position of the at leastone object 118. For this purpose, as will be explained with respect toFIG. 2A and the exemplary embodiment of one of the optical sensors 112depicted therein, each of the optical sensors 112 comprises a matrix 152of pixels 154. The detector 110, specifically the evaluation device 126,are adapted for determining an intensity distribution of the pixels 154of the at least one optical sensor 112 which are illuminated by thelight beam 150. The intensity distribution, as an example, may be adistribution of intensity values captured by the pixels 154 duringillumination by the light beam 150 or a distribution of numerical valuesderived thereof.

In this exemplary embodiment, the matrix 152 is a rectangular matrix, inwhich the pixels 154 are arranged in rows in an x-dimension and columnsin a y-dimension, as symbolically depicted by the coordinate system 146depicted in FIG. 2A. The plane of the matrix 152 may be perpendicular tothe optical axis 142 of the detector 110 and, thus, may be perpendicularto the longitudinal coordinate z. However, other embodiments arefeasible, such as embodiments having non-planar optical sensors 112and/or embodiments having non-rectangular matrices of pixels 154.

The detector 110 is adapted to determine a position of the object 118,and the optical sensor 112 is adapted to detect the light beam 150traveling from the object 118 towards the detector 110, specificallyfrom one or more of the beacon devices 116. For this purpose, theevaluation device 126 is adapted to determine at least one longitudinalcoordinate of the object 118 by using the intensity distribution of thepixels 154, as will be outlined in further detail below.

The light beam 150, directly and/or after being modified by the transferdevice 136, such as being focused by the lens 138, creates a light spot156 on a sensor surface 158 of the optical sensor 112 or of each of theoptical sensors 112. Each of the pixels 154 may be adapted to generatean individual signal, also referred to as an intensity value, as asensor signal or as a pixel signal, which represents an intensity ofillumination of the respective pixel. The entity or totality of sensorsignals of the pixels 154 or of values derived thereof may be regardedas an intensity distribution of the pixels.

Thus, as an example, in FIG. 2A, a multiplexing measuring scheme isdepicted which may be used for generating sensor signals for each of thepixels 154. Thus, each of the columns of the matrix 152 may be connectedto a respective current measurement device 160. A switch 162 may beprovided for contacting each of the rows of the matrix 152. Thus, amultiplexing measurement scheme may be implemented in which the rows ofthe matrix 152 are contacted sequentially. Thus, in a first step, theuppermost row of the matrix 152 may be contacted by switch 162, therebyallowing for measuring electrical currents through each of the pixels ofthe uppermost row of the matrix 152. The currents may be provided in ananalogue format and/or may be transformed into a digital format, such asby providing one or more analogue-digital-converters. Thus, measurementvalues for each of the pixels of the uppermost pixel row of matrix 152may be generated, such as by providing 4-bit grayscale values, 8-bitgrayscale values or other information formats. The respectiveinformation values representing the sensor signals of the pixels 154 maybe provided to the evaluation device 126, which may comprise one or morevolatile and/or non-volatile data memories 164. Subsequently, byswitching switch 162 to contact the second row of the matrix 152, sensorsignals for each bit of the second row are generated, followed by sensorvalues of the subsequent rows. After finishing one measurement of thecomplete matrix 152, the routine may start anew, such as by contactingthe first row of the matrix 152 again. Thus, by using this multiplexingscheme or other multiplexing schemes, sensor signals for each of thepixels 154 may be generated. Since the multiplexing may be performed ata high repetition rate, it may be assumed that neither the intensity ofthe light beam 150 nor the position of the light spot 156 changessignificantly during one multiplexing cycle. However, it shall be notedthat, specifically for fast moving objects 118, other schemes forgenerating sensor values may be used, such as measurement schemescreating sensor values for each pixel 154 of the matrix 152simultaneously.

As outlined above, preferably, the matrix 152 preferably contains atleast 10 pixel rows and at least 10 pixel columns. Thus, as an example,at least 20 pixel rows and at least 20 pixel columns may be present,preferably at least 50 pixel rows and 50 pixel columns and, morepreferably, at least 100 pixel rows and 100 pixel columns. Thus,specifically, standard formats may be used, such as VGA and/or SVGA.

The sensor signals provided by the pixels 154 may be used to determinethe position of the object 118. Thus, firstly, as outlined in FIG. 2A,the sensor signals of the pixels 154 may be compared, in order todetermine the one or more pixels having the highest intensity ofillumination by the light beam 150. This center of illumination, such asthe center of the light spot 156, may be used for determiningcoordinates x_(max) and y_(max), representing transversal coordinates ofthe light spot 156. By using known imaging equations, such as thewell-known lens equation, a transversal coordinate of the object 118and/or the respective beacon device 116 emitting the light beam 150 inthe coordinate system 146 may be determined from the coordinatesx_(max), y_(max). Thus, by determining a transversal position of thelight spot 156 on the sensor surface 158 of the optical sensor 112, atransversal position of the object 118 and/or a part of the object 118may be determined.

Further, as outlined above and as will be explained in further detailbelow, the detector 110 is adapted to determine a longitudinalcoordinate of the object 118 and/or of the at least one beacon device116, by using the intensity distribution. For this purpose, variousalgorithms may be used which will be explained by examples in furtherdetail below. Thus, generally, the evaluation device 126 may be adaptedto determine the longitudinal coordinate of the object 118 by using apredetermined relationship between the intensity distribution and thelongitudinal coordinate. Specifically, the evaluation device 126 may beadapted to determine at least one intensity distribution functionapproximating the intensity distribution. Thus, the evaluation device126 may be adapted to determine the longitudinal coordinate of theobject 118 by using a predetermined relationship between a longitudinalcoordinate and the intensity distribution function and/or at least oneparameter derived from the intensity distribution function. Theintensity distribution function, as an example, may be a beam shapefunction of the light beam 150, as will be explained with regard toFIGS. 8 to 13 below. The intensity distribution function specificallymay comprise a two-dimensional or a three-dimensional mathematicalfunction approximating an intensity information contained within atleast part of the pixels 154 of the optical sensor 112.

Additionally or alternatively, as will be outlined with respect to FIGS.2A and 2B below, the evaluation device 126 may be adapted to determinethe intensity distribution, wherein determining the intensitydistribution comprises determining a number N of pixels of the opticalsensor 112 which are illuminated by the light beam 150. The determiningof the at least one longitudinal coordinate of the object 118 maycomprise using the number N of pixels which are illuminated by the lightbeam 150, such as by using a predetermined relationship between thenumber N of pixels which are illuminated by the light beam 150 and thelongitudinal coordinate. These options may be combined in various ways.

Specifically, for the purpose of determining the longitudinalcoordinate, a diameter and/or equivalent diameter of the light spot 156may be evaluated, as will be explained in the following. The diameterand/or equivalent diameter may be determined in various ways, such as byusing the above-mentioned way of determining an intensity distributionfunction and/or by using the above-mentioned way of determining thenumber N of pixels of the optical sensor 112 which are illuminated bythe light beam 150. Even a combination of both options is feasible.

As outlined above, in an example, the evaluation device 126 may beadapted to determine a number N of pixels 152 which are illuminated bythe light beam 150. For this purpose, a threshold method may be used, inwhich the sensor signals of each of the pixels 154 are compared to oneor more thresholds determining whether the respective pixel 154 isilluminated or not. The one or more thresholds may determine aborderline 166 of the light spot 156, as depicted in FIG. 2A. As anexample, assuming a Gaussian illumination with a typical Gaussianintensity profile, the borderline 166 may be chosen as a line at whichthe intensity of the light spot 156 has dropped from a central intensityI₀ (which is the intensity at pixel coordinates x_(max), y_(max)) to1/e²·I₀.

The threshold method may easily be implemented, as an example, by usinga histogram analysis of the sensor values of one image (such as of onescan of a multiplexing scheme and/or of one image of pixelssimultaneously taken), as symbolically depicted in FIG. 2B. It shall benoted that the histogram analysis in FIG. 2B does not fully correspondto the image as depicted in FIG. 2A. In FIG. 2B, on a horizontal axis,the sensor signals of the pixels 154 acquired in one image, denoted by“I” (non withstanding the fact that other sensor signals than currentsmay be used, such as bit values or grayscale values), are given. On thevertical axis, denoted by “#”, the counts for each of the sensor signalsare given, i.e. the number of pixels 154 providing the respective sensorsignal I. Thus, as an example, grayscale values may be given on thehorizontal axis, and the number of pixels showing the respectivegrayscale values in one image may be given on the vertical axis. Thehighest sensor signal noted within this image is marked as I₀. Byproviding an appropriate threshold 1/e²·I₀ (and/or the closest integervalue to this threshold, such as the next integer value above 1/e²·I₀and/or the next integer value below 1/e²·I₀—within the presentinvention, these options shall be enclosed), as symbolically depicted inFIG. 2B, the pixel counts in this histogram analysis may be divided intocounts for non-illuminated pixels 154 (denoted by reference number 168in FIG. 2B and marked by white bars), i.e. the sensor signals of pixels154 outside the borderline 166 in FIG. 2A, and counts for illuminatedpixels (denoted by reference number 170 in FIG. 2B and marked by filledbars), i.e. pixels 154 within the borderline 166 in FIG. 2A. Thus, byusing this threshold method and/or other threshold methods, illuminatedpixels and non-illuminated pixels may be distinguished, such as by usingan appropriate histogram analysis.

This distinguishing of illuminated and non-illuminated pixels allows forcounting the number N of the pixels 154 which are illuminated by thelight beam 150. Thus, an integration over the illuminated pixels 170 inFIG. 2B and their respective counts leads to the number N of illuminatedpixels. Other methods for determining the number N of illuminated pixelsmay be used additionally or alternatively.

As given in equation (4) or, for a plurality of optical sensors 112, inequation (4′) above, the number N of illuminated pixels is proportionalto the area of the light spot 156. Thus, since the diameter of any typeof light beam 150 varies with propagation, by evaluating the number N ofilluminated pixels, a longitudinal coordinate of the object 118 or,specifically, of one or more beacon devices 116 emitting the respectivelight beam 150 may be determined. As an example, by assuming Gaussianproperties of the light beam 150, equations (6) and/or (6′) given abovemay be used. As an example, the light beam 150 itself may have Gaussianproperties. Additionally or alternatively, the at least one transferdevice 136 with the at least one optional lens 138 may be used forbeam-shaping wherein, still, the spatial information on the longitudinalposition of the object 118 or, specifically, the respective beacondevice 116, is contained in the propagation properties of the shapedlight beam 150.

In case the detector 110 has a narrow viewing angle, the distancebetween the object 118 and the detector 110 may be considered a distancein the z-dimension, only. However, since, by using the matrix 152 ande.g. the algorithm given above, transversal coordinates x and/or y maybe determined in addition, the full traveling distance of the light beam150 may easily be calculated, taking into account an offset of therespective beacon device 116 from the optical axis 152. Specifically,for objects which are located off-axis, reference may be made to theexplanations regarding FIG. 5 below.

As outlined above, preferably, a plurality of the optical sensors 112 isprovided, such as by providing the sensor stack 148. The redundancy ofthe optical sensors 112 may be used in various ways.

Thus, as outlined above, by determining the number N of illuminatedpixels for one of the optical sensors 112, a beam waste may bedetermined. However, as may easily be derived from one or more ofequations (3), (6) or (6′) given above, the longitudinal coordinate zderived thereby is ambiguous with respect to the focal point. Thus, bysimply determining one beam waste and/or one number N of illuminatedpixels, uncertainty may arise whether the respective image was taken ata specific distance z before or after a focal point of the Gaussianlight beam 150. This ambiguousness may be resolved in various ways.Thus, firstly, a movement of the detector 110 and/or the object 118 maybe tracked, such as by using a series of images and/or a trackcontroller 172 of the tracking system 124. Thus, a history of movementsof the object 118 may be tracked, providing additional spatialinformation of the object 118 may allow for determining whether therespective optical sensor 112 is positioned before or after a focalpoint of the light beam 150. Additionally or alternatively, however, aswill be explained with respect to FIGS. 3A and 3B, a redundancy ofinformation provided by the optical sensor stack 148 may be used forresolving this ambiguousness of the longitudinal coordinate. Thus, inFIG. 3A, a side view of a simplified beam path of the light beam 150,traveling from one or more of the beacon devices 116 towards thedetector 110, is depicted. As can be seen, due to Gaussian beampropagation properties, the light beam 150 within the sensor stack 148narrows, up to a focal point 174, which, in this exemplary embodiment,occurs close to the middle one of the optical sensors 112. Otherembodiments of the beam path are feasible. In FIG. 3B, views of thesensor surfaces 158 of the optical sensors and the respective lightspots 156 for each of the optical sensors 112 of the setup in FIG. 3Aare given. The optical sensors 112 are numbered by numbers 1 through 5,as in FIG. 3A. As can be seen, the light spot 156 in the middle opticalsensor 112, close to the focal point 174, is smallest, whereas thediameter of the light spots 156 to the right and to the left of thismiddle sensor (sensor number 3) widens. As can be seen by comparing thediameter of the light spots 156 of the optical sensors 1 and 5 or 2 and4, the diameter is ambiguous. However, by comparing a specific diameterwith diameters of light spots of neighboring optical sensors, it may bedetermined whether the light beam widens or narrows, i.e. whether therespective optical sensor 112 is positioned before or after the focalpoint 174. Thus, the above-mentioned ambiguousness may be resolved, anda z-coordinate may be determined, such as in the coordinate system 146and/or in another coordinate system.

The optical sensors 112 of the sensor stack 148, as outlined above,preferably are transparent to the light beam 150. For the last opticalsensor 112 of the sensor stack 148, facing away from the object 118,such as the optical sensor 112 named “5” in FIG. 3A, a transparency notnecessarily has to be present. Thus, this last optical sensor 112 mayalso be intransparent.

As further outlined above, providing a plurality of the optical sensors112, such as in a stacked fashion, may, additionally or alternatively,also be used for other purposes. Thus, the optical sensors 112 mayprovide different spectral sensitivities, in order to provide at leastone information on a color of the light beam 150. Thus, in FIG. 3C,extinction coefficients of three of the optical sensors 112 are given asa function of the wavelength λ. These extinction coefficients or anyother measure indicating a spectrum of absorption of the respectiveoptical sensors 112, may be adjusted by providing appropriate absorptivematerials, such as appropriate dyes, within the optical sensors 112. Asan example, in case the optical sensors 112 comprise dye-sensitizedsolar cells (DSCs, specifically sDSCs), an appropriate dye may bechosen. As an example, in FIG. 3C, different spectral sensitivities(such as normalized sensitivities) ε are given for optical sensors 1, 2and 3, as an example, as a function of the wavelength λ. Assuming thatthe total power of the light beam remains identical for all light spots156 on the sensor surfaces 158, or, with known attenuation of the lightbeam 150 after passing a specific optical sensor 112, a ratio of thesensor signals of the respective optical sensors 112 having differentabsorption properties may be used for determining a color of the lightbeam 150. As an example, for each of the optical sensors 112, a totalsensor signal may be determined by adding the sensor signals of each ofthe pixels 154. Alternatively, a respective representative sensor signalfor each of the optical sensors 112 may be determined, such as a peakvalue or maximum value of the sensor signals. Again, alternatively, thesensor signals of the pixels 154 within the light spots 156 may beintegrated, thereby generating a representative sensor signal for eachof the optical sensors 112. In the exemplary embodiment depicted in FIG.3C, an information on a green component of the light beam 150, e.g., maybe determined by dividing the sensor signal of the third optical sensor112 (sensor number 3) by a sum of the sensor signals of optical sensors1, 2 and 3. Similarly, a yellow component of the light beam 150 may bedetermined by dividing the sensor signal of the first optical sensor bya sum of the sensor signals of optical sensors 1, 2 and 3. Again,similarly, a red component of the light beam 150 may be determined bydividing the sensor signal of the second optical sensor 112 by a sum ofthe sensor signals of optical sensors 1, 2 and 3. Other embodimentsand/or algorithms for determining colors are feasible. Thus, as anexample, the absorption spectra of three of the optical sensors 112 maybe similar to the absorption materials used as a basis of theabove-mentioned CIE coordinate system, thereby directly allowing fordetermining CIE coordinates of the light beam 150. It shall be notedthat the determination of the color of the light beam 150 is independentfrom the above-described determination of the longitudinal coordinate ofthe object 118, since the above-mentioned algorithm is simply based on acounting of illuminated and non-illuminated pixels, independent from thecolor of the light beam 150. Thus, e.g. in the threshold method andhistogram analysis described with regard to FIGS. 2A and 2B above, aninternal normalization of the intensity of the light beam and/or thecolor of the light beam may take place, since, as outlined above, thethreshold may be chosen as a function and/or fraction of a maximumintensity and/or of a maximum sensor signal. Thus, the determination ofthe longitudinal coordinate by using the above-mentioned pixel count isindependent from the fact that the respective optical sensors 112 withinthe sensor stack 148 may have different spectral absorption properties.

As outlined above, the determination of a position of the object 118and/or a part thereof by using the detector 110 may be used forproviding a human-machine interface 120, in order to provide at leastone item of information to a machine 176. In the embodimentschematically depicted in FIG. 1, the machine 176 may be a computerand/or may comprise a computer. Other embodiments are feasible. Theevaluation device 126 even may fully or partially be integrated into themachine 176, such as into the computer. The same holds true for thetrack controller 172, which may also fully or partially form part of thecomputer of the machine 176.

Similarly, as outlined above, the human-machine interface 120 may formpart of an entertainment device 122. The machine 176, specifically thecomputer, may also form part of the entertainment device 122. Thus, bymeans of the user 134 functioning as the object 118 and/or by means ofthe user 134 handling a control device 132 functioning as the object118, the user 134 may input at least one item of information, such as atleast one control command, into the computer, thereby varying theentertainment function, such as controlling the course of a computergame.

As outlined above, the one optical sensor 112 and/or one or more of theoptical sensors 112 preferably may fully or partially be transparentwith regard to the light beam 150. In FIGS. 4A to 4C, an exemplary setupof a transparent optical sensor 112 is depicted in various views.Therein, FIG. 4A shows a top view, FIG. 4B shows a cross-sectional viewalong line A-A in FIG. 4A, and FIG. 4C shows a cross-sectional viewalong line B-B in FIG. 4A.

The optical sensor 112 may comprise a transparent substrate 178, such asa glass substrate and/or a plastic substrate. For potential details ofthe substrate 178, reference may be made to documents WO 2012/110924 A1and U.S. provisional applications Nos. 61/739,173 and/or 61/749,964.However, other embodiments are feasible. The illumination by the lightbeam 150 may take place through the substrate 178 and/or from anopposite side. Thus, the bottom side of the substrate 178 in FIG. 4B mayform the sensor surface 158. Alternatively, an illumination from theopposing surface may take place.

On top of the substrate 178, a first electrode 180 is deposited, which,in this embodiment, may comprise a plurality of first electrode stripes182. Preferably, the first electrode 180 is fully or partiallytransparent. Thus, as an example, the first electrode 180 may fully orpartially be made of a transparent conductive oxide, such asfluorine-doped tin oxide (FTO) and/or indium-doped tin oxide (ITO). Forfurther details of the first electrode 180, reference may be made to WO2012/110924 A1 and/or one or more of U.S. provisional applications Nos.61/739,173 and/or 61/749,964. However, other embodiments are feasible. Apatterning of the first electrode stripes 182 may take place byappropriate patterning techniques which are generally known to theskilled person in the field of display technology, e.g. etching and/orlithographic techniques. Thus, as an example, a large-area coating bythe material of the first electrode 180 on the substrate 178 may beprovided, wherein the areas of the first electrode stripes 182 may becovered by photoresist and wherein the uncovered regions may be etchedby an appropriate etching means, as known to the skilled person in thetechnical field of display manufacturing, such as LCD manufacturing.

On top of the first electrode 180, one or more light-sensitive layers184, such as a light-sensitive layer setup comprising one, two, three ormore layers, are deposited. As an example, the light-sensitive layers184 may comprise a layer setup of a dye-sensitized solar cell (DSC),more specifically of a solid dye-sensitized solar cell (sDSC), such asdisclosed in WO 2012/110924 A1 and/or one or more of the U.S.provisional applications 61/739,173 and/or 61/749,964. Thus, thelight-sensitive layers 184 may comprise one or more layers of ann-semiconducting metal oxide, preferably a nanoporous metal oxide, suchas TiO₂, which may directly or indirectly be deposited on top of thefirst electrode 180. Further, the n-semiconducting metal oxide may fullyor partially be sensitized with one or more dyes, such as one or moreorganic dyes, preferably one or more of the dyes disclosed in WO2012/110924 A1 and/or one or more of U.S. provisional applications No.61/739,173 and/or 61/749,964. Other embodiments are feasible.

On top of the dye-sensitized n-semiconducting metal oxide, one or morelayers of a p-semiconducting and/or conducting material may bedeposited. Thus, preferably, one or more solid p-semiconducting organicmaterials may be used which may directly or indirectly be deposited ontop of the n-semiconducting metal oxide. As an example, reference may bemade to one or more of the p-semiconducting materials as disclosed in WO2012/110924 A1 and/or as disclosed in one or more of U.S. provisionalapplications no. 61/739,173 and/or 61/749,964. As a preferred example,Spiro-MeOTAD may be used.

It shall be noted that the named light-sensitive layers 184, whichpreferably may comprise one or more organic light-sensitive layers 184,may also be provided in a different layer setup. Thus, basically, anytype of light-sensitive material, such as an organic, inorganic orhybrid layer setup, may be used, which is adapted to provide an electricsignal in accordance with an illumination of the layer setup.

As can be seen specifically in the top view of FIG. 4A, the one or morelight-sensitive layers 184 preferably are patterned such that one ormore contact areas 186 for contacting the first electrode stripes 182remain uncovered by the light-sensitive layer 184. This patterning maybe performed in various ways. Thus, a large-area coating of thelight-sensitive layers 184 may be applied, and the contact areas 186may, subsequently, be uncovered, such as by laser ablation and/ormechanical ablation. Additionally or alternatively, however, the one ormore light-sensitive layers 184 may fully or partially be applied to thesetup in a patterned way, such as by using appropriate printingtechniques. Combinations of the named techniques are feasible.

On top of the at least one light-sensitive layer 184, at least onesecond electrode 188 is deposited. Again, this at least one secondelectrode 188 preferably may comprise a plurality of electrode stripes,which, in this embodiment, are denoted by reference number 190 (secondelectrode stripes). As can be seen specifically in the top view of FIG.4A, the second electrode stripes 190 preferably are oriented essentiallyperpendicular to the first electrode stripes 182, such as at an angle of90°±20°, preferably 90°±10° and more preferably 90°±5°. It shall benoted, however, that other electrode geometries for the first electrode180 and the second electrode 188 are feasible.

As can be seen in the top view of FIG. 4A, each of the second electrodestripes 190 comprises at least one contact area 192 which allows for anelectrical contacting of the second electrode stripes 190.

As further may be derived from the top view in FIG. 4A, the layer setupof the optical sensor 112 provides a plurality of areas in which thesecond electrode stripes 190 cross the first electrode stripes 182. Eachof these areas, by itself, forms an individual optical sensor, which isalso referred to as a pixel 154 and which may be contacted electricallyby electrically contacting the appropriate contact areas 186, 192 of therespective electrode stripes 182, 190. Thus, by measuring an electricalcurrent through these individual optical sensors, each of the pixels 154may provide an individual optical signal, as explained above. In thisembodiment, the pixels 154 may be arranged in a rectangular setup,forming a rectangular matrix 152. It shall be noted, however, that othersetups are feasible, such as non-rectangular matrix setups. Thus, as anexample, honeycomb structures or other geometric setups may be realized.

In addition to the layer setup shown in FIGS. 4A to 4C, the opticalsensor 112 may comprise one or more encapsulation elements, such as oneor more encapsulation layers and/or one or more cover elements, such asglass lids and/or plastic lids. The latter, for example, may be glued ontop of the layer setup shown e.g. in FIGS. 4B and 4C, preferably byleaving open the contact areas 186, 192.

The second electrode stripes 190 preferably may comprise one or moremetal layers, such as one or more layers of a metal selected from thegroup consisting of: Al, Ag, Au, Pt, Cu. Additionally or alternatively,combinations of two or more metals may be used, such as metal alloys. Asan example, one or more metal alloys selected from the group of NiCr,AlNiCr, MoNb and AlNd may be used. Still, other embodiments arefeasible. Preferably, as for the first electrode stripes 182, the secondelectrode stripes 190 may fully or partially be transparent. Thistransparency may be realized in various ways. Thus, as an example, thinmetal layers may be used, such as metal layers having a thickness ofbelow 50 nm, such as a thickness of ≤30 nm or ≤20 nm. At these layerthicknesses, the typical metals still are transparent. Additionally oralternatively, however, non-metallic conductive materials may be used,such as conductive polymers. As an example, PEDOT:PSS and/or PANI may beused. For further potential details of the setup of the second electrode188, reference may be made to WO 2012/110924 A1, U.S. 61/739,173 and/or61/749,964, as mentioned above.

The second electrode stripes 190 may be applied to the layer setup byusing typical application techniques. Thus, as an example, one or moremetal layers may be deposited by using physical vapor deposition (suchas evaporation and/or sputtering). Conductive non-metallic materials,such as conductive polymers, may e.g. be applied by using typicalcoating techniques, such as spin-coating and/or printing. Othertechniques are feasible. The patterning of the second electrode stripes190 may be performed in various ways. Thus, when using evaporationtechniques and/or vacuum deposition techniques, a mask technique may beused, such as evaporation through shadow masks. Additionally oralternatively, printing may be performed in a patterned way. Thus, as anexample, screen-printing and/or inkjet-printing may be used forpatterning conductive polymers. Again, additionally or alternatively,one or more separating patterns may be provided on the layer setupand/or on the substrate 178, such as photoresist patterns, whichsub-divide the second electrode 188 into the second electrode stripes190.

It shall further be noted that the layer setup of the first electrode180, the one or more light-sensitive layers 184 and the second electrode188 may as well be inverted. Thus, as an example, the layer setup of theDSC, specifically the sDSC, may be inverted, as compared to the layersetup described above. Further, additionally or alternatively, the setupof the electrodes 180, 188 may be inverted, thus providing the secondelectrode 188 on the substrate 178, providing the one or morelight-sensitive layers 184 directly or indirectly on top of this secondelectrode, and providing the first electrode 180 on top of this at leastone light-sensitive layer 184. Various variations of the setup arefeasible. Further, it shall be noted that one or more of electrodes 180,188 may as well be intransparent. Thus, as explained above, a detector110 having only one optical sensor 112 is feasible. In this case, theoptical sensor 112 not necessarily has to be transparent. Thus, as anexample, the second electrode 188 may be intransparent, such as by usingthick metal layers, in case light is transmitted into the optical sensor112 via sensor surface 158. In case light is transmitted into theoptical sensor 112 from the other side, the first electrode 180 may bean intransparent electrode. Further, in case a sensor stack 148 is used,as e.g. in the setup of FIG. 1, the last optical sensor 112 of thesensor stack 148, facing away from the object 118, not necessarily hasto be transparent. Thus, an intransparent optical sensor 112 may beused.

In FIG. 5, in addition to the explanations given above with regard toFIGS. 2A to 3B, a further embodiment of a detector 110 and of a camera111 are shown in a partial perspective view, which, in the following,will be used for further explaining an embodiment for determining theposition of at least one object 118 (not shown in this figure) emittinga light beam 150. The detector 110 and/or the camera 111 may be part ofa detector system 114, a human-machine interface 120, an entertainmentdevice 122 or a tracking system 124 and may comprise additionalcomponents which are not depicted in FIG. 5. Thus, as an example, theevaluation device 126 is not depicted. With regard to potentialembodiments of the evaluation device 126 and/or with regard to furtherdetails, reference may be made to the embodiments shown above.

As can be seen, in this preferred embodiment, the detector 110, again,comprises a plurality of optical sensors 112, which, again, are arrangedin a sensor stack 148. For potential embodiments of the optical sensors112 and the sensor stack 148, reference may be made to the embodimentsdisclosed above.

The sensor stack 148 comprises at least two optical sensors 112,wherein, in this embodiment, only two optical sensors 112 are shown, oneoptical sensor 112 facing towards the object 118, of the last opticalsensor 112 in FIG. 5) and one optical sensor 112 facing away from theobject 118 (right optical sensor 112). Preferably, at least one of theoptical sensors 112 is at least partially transparent with regard to thelight beam 150, such that at least part of the light beam 150, in anunattenuated fashion or in an attenuated fashion, with unchangedspectral properties or modified spectral properties, may pass throughthe optical sensor 112. Thus, in FIG. 5, the left optical sensor 112 mayfully or partially be transparent, whereas the right optical sensor 112may be intransparent or transparent.

The light beam 150 may propagate in a direction of propagation 194,along an axis of propagation 196, which may be parallel or nonparallelto the z-axis which, preferably, is oriented orthogonally to the sensorsurfaces 158 of the optical sensors 112.

As outlined above with regard to FIGS. 2A and 2B, and as outlined abovewith regard to FIGS. 3A and 3B, light spots 156 created by the lightbeam 150 on the optical sensors 112 may be evaluated. Thus, as outlinedabove, for one or more of the light spots 156, a center 198 may bedetermined, at least within the boundaries of resolution given by thepixels 154. As an example, in FIG. 5, the optical sensors 112 containmatrices 152 of pixels 154, wherein each pixel is characterized by itsrow (symbolically denoted by row identifier A to I in FIG. 5) and itscolumn (symbolically denoted by column identifier 1 to 7 in FIG. 5).Other embodiments of identifying pixel coordinates are feasible, such asby using numbers both as row identifiers and as column identifiers.Thus, in the exemplary embodiment shown in FIG. 5, the center 198 of thelight spot 156 for the left optical sensor 112 may be identified to belocated in between rows D and E and in between columns 4 and 5, whereasthe center 198 of the light spot 156 on the right optical sensor 112 maybe identified to be located in row D and column 6. Thus, by connectingthe centers 198, the axis of propagation 196 of the light beam 150 mayeasily be determined. Consequently, the direction of the object 118 withregard to the detector 110 may be determined. Thus, since the center 198of the light spot 156 on the right optical sensor 112 is shifted towardsthe right (i.e. towards higher column numbers), it may be determinedthat the object 118 is located off centered from the z-Axis towards theright.

Further, as outlined above, by evaluating beam waist w₀, a longitudinalcoordinate of the object 118 may be determined. Thus, as an example, thebeam waist may be dependent on the longitudinal coordinate according toone or more of the above-mentioned relationships, specifically accordingto a Gaussian relationship. In case the direction of propagation 194 isnon-parallel to the optical axis or z-coordinate, as depicted in FIG. 5,the longitudinal coordinate of the object 118 may be a coordinate alongthe axis of propagation 196. Since, e.g. by comparing the coordinates ofthe centers 198, the axis of propagation 196 may easily be determined,and angular relationship between the z-axis and the axis of propagation196 is known, and, thus, a coordinate transformation is easily possible.Thus, generally, by evaluating the pixel counts of one or more opticalsensors 112, the position of the object 118 may be determined. Further,since each of the optical sensors 112 may be used for generating animage of the object 118 and since the longitudinal coordinate of theobject 118 and/or of one or more points of the object 118 are known, athree-dimensional image of the object 118 may be generated.

As outlined above, counting the number N of pixels of the optical sensor112 which are illuminated by the light beam 150 is one option ofevaluating the intensity distribution of the pixels 154. Additionally oralternatively, the evaluation device 126 may be adapted to determine atleast one intensity distribution function approximating the intensitydistribution, as will be explained with respect to FIGS. 8 to 13. Thus,the evaluation device 126 may be adapted to determine the longitudinalcoordinate of the object 118 by using a predetermined relationshipbetween a longitudinal coordinate and the intensity distributionfunction and/or at least one parameter derived from the intensitydistribution function. The intensity distribution function, as anexample, may be a beam shape function of the light beam 150, as will beexplained with regard to FIGS. 8 to 13 below. The intensity distributionfunction specifically may comprise a two-dimensional or athree-dimensional mathematical function approximating an intensityinformation contained within at least part of the pixels 154 of theoptical sensor 112.

Thus, FIGS. 8 through 13 show exemplary embodiments of determiningintensity distribution functions of the intensity distribution of thepixels 154 of the matrix 152. In these embodiments, as an example,two-dimensional functions are determined by using appropriate fittingalgorithms. Therein, in FIGS. 8 through 13, intensity distributions aregiven by indicating an intensity value I on a vertical axis, given inarbitrary units, as a function of an identifier p of the respectivepixel on the horizontal axis. As an example, pixels 154 along line A-Ain FIG. 2A, such as a line through the center of the light spot 156, maybe depicted and identified by their vertical coordinate p. Similarly,the evaluation may be performed for each of the optical sensors 112 inFIGS. 3A and 3B, as indicated by horizontal lines A-A in the images ofFIG. 3B.

FIGS. 8 through 13 show exemplary embodiments of intensity distributionsgenerated by a single optical sensor 112, wherein the intensities of thesingle pixels 154 are shown as bars. It shall be noted, however, that,instead of evaluating intensity distributions along a line A-A, othertypes of evaluations are feasible, such as three-dimensional evaluationsevaluating all pixels 154 within the matrix 152, such as by usingthree-dimensional intensity distribution functions. Further, instead ofevaluating a single matrix 152 of a single optical sensor 112 or a partthereof, two or more optical sensors 112 may be evaluated, such as theoptical sensors 112 of the sensor stack 148.

As outlined above, in FIGS. 8 through 13, the intensities of the pixels154 are shown as bars. The evaluation device 126 may be adapted todetermine intensity distribution functions, which are shown in thesefigures as solid lines. As outlined above, the determination of theintensity distribution functions may be performed by using one or morefitting algorithms, thereby e.g. fitting one or more predeterminedfitting functions to the actual intensity distributions. As an example,as outlined above, one or more mathematical functions may be used, suchas one or more mathematical function selected from the group consistingof: a bell-shaped function; a Gaussian distribution function; a Besselfunction; a Hermite-Gaussian function; a Laguerre-Gaussian function; aLorentz distribution function; a binomial distribution function; aPoisson distribution function; at least one derivative, at least onelinear combination or at least one product comprising one or more of thebefore-mentioned functions. Thus, a single mathematical function or acombination of two or more identical or similar or non-identicalmathematical functions may be used as fitting functions and may befitted to the actual intensity distributions, thereby generating theintensity distribution functions, such as by adapting one or moreparameters of these fitting functions.

Thus, as an example, FIG. 8 shows a cut through a Gaussian beam measuredby 16 pixels. The fitted Gaussian function which represents theintensity distribution function is plotted as a solid line. FIG. 9demonstrates that the evaluation may even be performed in case two ormore light beams 150 are present, generating two or more light spots156. Thus, in FIG. 9, a cut through two Gaussian beams measured by 16pixels is shown. The fitted Gaussian functions representing twointensity distribution functions are plotted as solid lines in FIG. 9.

Further evaluation of the intensity distributions may be performed asfor the case of counting illuminated pixels demonstrated above. Thus,one or more parameters may be determined from the fitted mathematicalfunctions. Thus, as demonstrated by formulae (2) and (3) above, one ormore beam waists w may be determined from the fitted Gaussian functionin FIG. 8 or for each of the fitted Gaussian functions in FIG. 9. Thebeam waist may be used as a measure for the diameter or equivalentdiameter of the light spot 156. Additionally or alternatively, otherparameters may be derived.

By using one or more of the parameters derived, the at least onelongitudinal coordinate of the object 118 may be determined, asexplained with respect to FIG. 2A, 2B, 3A-3C or 5 above. Thus, as anexample, the longitudinal coordinate of the object 118 may be determinedby using equation (3) above. Further, as outlined above, a sensor stack148 may be used. The evaluation shown in FIG. 8 or 9 or any other typeof determining an intensity distribution function may be applied to twoor more or even all of the optical sensors 112 of the sensor stack 148.Thus, as an example, the evaluation shown in FIG. 8 or 9 may beperformed for each of the optical sensors 112 of the stack, therebyderiving a beam diameter or a measure indicating the beam diameter foreach of the optical sensors 112. Thereby, three-dimensional images maybe generated and evaluated, and, as outlined above with respect to FIGS.3A and 3B, ambiguities may be resolved. Further, besides a single colorevaluation, multicolor evaluation as explained with respect to FIG. 3Cmay be performed.

In FIGS. 10 through 13, exemplary embodiments are shown whichdemonstrate that the evaluation is not restricted to Gaussian intensitydistributions and Gaussian intensity distribution functions. Thus, FIG.10 shows a cut through a square-shaped object measured by 16 pixels.Again, the measured pixel currents, indicating the intensitydistribution, are plotted as bars. The intensity distribution functionfitted to the intensity distribution, implementing a beam shape functionor a fitted edge shape function, is given as a solid line. In thisembodiment of FIG. 10, as an example, the square-shaped object 118, e.g.imaged by the transfer device 136 onto the optical sensor 112, is infocus, thereby generating sharp edges. In FIGS. 11 through 13, theobject 118 is moving out of focus, thereby generating blurred edges.Thus, FIG. 11 shows the intensity distribution of the square-shapedobject 118 of FIG. 10, slightly out of focus. In FIG. 12, thesquare-shaped object 118 is out of focus, and edges are becomingblurred. In FIG. 13, the square-shaped object 118 is further out offocus, inducing a further blurring of the edges and an overall blurredshape of the intensity distribution. As an example, FIGS. 10 through 13may be images generated by the different optical sensors 112 of thesensor stack 148, with the optical sensors 112 having differingdistances from a focal plane. Additionally or alternatively, the imagesof FIGS. 10 through 13 may be generated by moving the object 118 alongthe optical axis 142, thereby varying the intensity distributions. Sincethe imaging properties of the transfer device 136 are generally wellknown and since beam propagation properties and imaging may becalculated by standard optical methods, the position of the object 118or at least one longitudinal coordinate of the object 118 may bedetermined by evaluating the intensity distribution functions, as theskilled person will know, similar to using equation (3) given above forGaussian light beams.

In FIG. 6, a schematic setup of a detector 110 according to the presentinvention to be used as a light-field camera is shown. Basically, thesetup shown in FIG. 6 may correspond to the embodiment shown in FIG. 1or any other of the embodiments shown herein. The detector 110 comprisesa sensor stack 148 of optical sensors 112, also referred to as pixelatedsensors, which specifically may be transparent. As an example, pixelatedorganic optical sensors may be used, such as organic solar cells,specifically sDSCs. In addition, the detector 110 may comprise at leastone transfer device 136 such as at least one lens 138 or lens system,adapted for imaging objects 118. Additionally, in this embodiment orother embodiments, the detector 110 may comprise at least one imagingdevice 196, such as a CCD and/or a CMOS imaging device.

As outlined above, the detector 110 in the embodiment shown herein issuited to act as a light-field camera. Thus, light-beams 150 propagatingfrom various objects 118 or beacon devices 116, symbolically denoted byA, B and C in FIG. 6, are focused by the transfer device 136 intocorresponding images, denoted by A′, B′ and C′ in FIG. 6. By using thestack 148 of optical sensors 112, a three-dimensional image may becaptured. Thus, specifically in case the optical sensors 112 areFiP-sensors, i.e. sensors for which the sensor signals are dependent onthe photon density, the focal points for each of the light beams 150 maybe determined by evaluating sensor signals of neighboring opticalsensors 112. Thus, by evaluating the sensor signals of the stack 148,beam parameters of the various light beams 150 may be determined, suchas a focal position, spreading parameters or other parameters. Thus, asan example, each light beam 150 and/or one or more light beams 150 ofinterest may be determined in terms of their beam parameters and may berepresented by a parameter representation and/or vector representation.Thus, since the optical qualities and properties of the transfer device136 are generally known, as soon as the beam parameters of the lightbeams 150 are determined by using the stack 148, a scene captured by theoptical detector 110, containing one or more objects 118, may berepresented by a simplified set of beam parameters. For further detailsof the light-field camera shown in FIG. 6, reference may be made to thedescription of the various possibilities given above.

Further, as outlined above, the optical sensors 112 of the stack 148 ofoptical sensors may have identical or different wavelengthsensitivities. Thus, the stack 148 may, besides the optional imagingdevice 196, comprise two types of optical sensors 112, such as in analternating fashion. Therein, a first type and a second type of opticalsensors 112 may be provided in the stack 148. The optical sensors 112 ofthe first type and the second type specifically may be arranged in analternating fashion along the optical axis 142. The optical sensors 112of the first type may have a first spectral sensitivity, such as a firstabsorption spectrum, such as a first absorption spectrum defined by afirst dye, and the optical sensors 112 of the second type may have asecond spectral sensitivity different from the first spectralsensitivity, such as a second absorption spectrum, such as a secondabsorption spectrum defined by a second dye. By evaluating sensorsignals of these two or more types of optical sensors 112, colorinformation may be obtained. Thus, in addition to the beam parameterswhich may be derived, the two or more types of optical sensors 112 mayallow for deriving additional color information, such as for deriving afull-color three-dimensional image. Thus, as an example, colorinformation may be derived by comparing the sensor signals of theoptical sensors 112 of different color with values stored in a look-uptable. Thus, the setup of FIG. 6 may be embodied as a monochrome, afull-color or multicolor light-field camera.

As outlined above, the detector 110 may further comprise one or moretime-of-flight detectors. This possibility is shown in FIG. 7. Thedetector 110, firstly, comprises at least one component comprising theone or more pixelated optical sensors 112, such as a sensor stack 148.In the embodiment shown in FIG. 7, the at least one unit comprising theoptical sensors 112 is denoted as a camera 111. It shall be noted,however, that other embodiments are feasible. For details of potentialsetups of the camera 111, reference may be made to the setups shownabove, such as the embodiment shown in FIG. 1, or other embodiments ofthe detector 110. Basically any setup of the detector 110 as disclosedabove may also be used in the context of the embodiment shown in FIG. 7.

Further, the detector 110 comprises at least one time-of-flight (ToF)detector 198. As shown in FIG. 7, the ToF detector 198 may be connectedto the evaluation device 126 of the detector 110 or may be provided witha separate evaluation device. As outlined above, the ToF detector 198may be adapted, by emitting and receiving pulses 200, as symbolicallydepicted in FIG. 7, to determine a distance between the detector 110 andthe object 118 or, in other words, a z-coordinate along the optical axis142.

The at least one optional ToF detector 198 may be combined with the atleast one detector having the pixelated optical sensors 112 such as thecamera 111 in various ways. Thus, as an example and as shown in FIG. 7,the at least one camera 111 may be located in a first partial beam path202, and the ToF detector 198 may be located in a second partial beampath 204. The partial beam paths 202, 204 may be separated and/orcombined by at least one beam-splitting element 206. As an example, thebeam-splitting element 206 may be a wavelength-indifferentbeam-splitting element 206, such as a semi-transparent mirror.Additionally or alternatively, a wavelength-dependency may be provided,thereby allowing for separating different wavelengths. As analternative, or in addition to the setup shown in FIG. 7, other setupsof the ToF detector 198 may be used. Thus, the camera 111 and the ToFdetector 198 may be arranged in line, such as by arranging the ToFdetector 198 behind the camera 111. In this case, preferably, nointransparent optical sensor is provided in the camera 111, and alloptical sensors 112 are at least partially transparent. Again, as analternative or in addition, the ToF detector 198 may also be arrangedindependently from the camera 111, and different light paths may beused, without combining the light paths. Various setups are feasible.

As outlined above, the ToF detector 198 and the camera 111 may becombined in a beneficial way, for various purposes, such as forresolving ambiguities, for increasing the range of weather conditions inwhich the optical detector 110 may be used, or for extending a distancerange between the object 118 and the optical detector 110. For furtherdetails, reference may be made to the description above.

LIST OF REFERENCE NUMBERS

-   110 detector-   111 camera-   112 optical sensor-   114 detector system-   116 beacon device-   118 object-   120 human-machine interface-   122 entertainment device-   124 tracking system-   126 evaluation device-   128 connector-   130 housing-   132 control device-   134 user-   136 transfer device-   138 lens-   140 opening-   142 optical axis-   144 direction of view-   146 coordinate system-   148 sensor stack-   150 light beam-   152 matrix-   154 pixel-   156 light spot-   158 sensor surface-   160 current measurement device-   162 switch-   164 data memory-   166 borderline-   168 non-illuminated pixels-   170 illuminated pixels-   172 track controller-   174 focal point-   176 machine-   178 substrate-   180 first electrode-   182 first electrode stripes-   184 light-sensitive layer-   186 contact area-   188 second electrode-   190 second electrode stripes-   192 contact area-   194 direction of propagation-   192 axis of propagation-   194 center-   196 imaging device-   198 time-of-flight detector-   200 pulses-   202 first partial beam path-   204 second partial beam path-   206 beam-splitting element

The invention claimed is:
 1. A detector for determining a position of atleast one object, the detector comprising: at least one optical sensor,the optical sensor being adapted to detect a light beam traveling fromthe object towards the detector, the optical sensor having at least onematrix of pixels; and at least one evaluation device, the evaluationdevice being adapted to determine an intensity distribution functionapproximating an intensity distribution of pixels of the optical sensorwhich are illuminated by the light beam and to determine at least onelongitudinal coordinate of the object from said intensity distributionfunction, wherein said intensity distribution function is atwo-dimensional intensity distribution function along an axis or linethrough the matrix.
 2. The detector according to claim 1, wherein saidtwo-dimensional intensity distribution function along an axis or linethrough the matrix is a cross-sectional axis through a center ofillumination by the light beam.
 3. The detector according to claim 2,wherein said center of illumination by the light beam is determined bythe optical sensor pixels having the highest illumination.
 4. Thedetector according to claim 1, wherein said two-dimensional intensitydistribution function along an axis or line through be matrix depends ona transversal beam profile of the light beam.
 5. The detector accordingto claim 1, wherein the evaluation device is adapted to determine thelongitudinal coordinate of the object through a predeterminedrelationship between the intensity distribution and the longitudinalcoordinate.
 6. The detector according to claim 1, wherein e evaluationdevice is adapted to determine the longitudinal coordinate of the objectthrough a predetermined relationship between a longitudinal coordinateand the intensity distribution function.
 7. The detector according toclaim 1, wherein the evaluation device is adapted to determine thelongitudinal coordinate of the object through a predeterminedrelationship between a longitudinal coordinate and at least oneparameter derived from the intensity distribution function.
 8. Thedetector according to claim 1, wherein the intensity distributionfunction is at least one of point symmetric or rotationally symmetric.9. The detector according to claim 1, wherein the intensity distributionfunction is mirror symmetric.
 10. A camera, the camera comprising atleast one detector according to claim
 1. 11. A mobile device, the mobiledevice comprising at least one detector according to claim 1.